I can't install pop_os! on a partition of a disk with windows installed

Question

I have been trying to install pop_os! for weeks... At this point I feel so stupid... trying different solutions like changing partition sizes, disabling safe boot mode or windows fast boot, trying to find similar errors on google... Nothing has worked, the pop_os! installation always throws the following error message after 1-2 minutes:

I have finally collected the logs of my pop_os installation and made screenshots of how the disks are partitioned:

Here above I cannot understand why pop forces me to format into a ext4 partition... In gparted is formatted as FAT32!!! And so it should be /boot/efi right??... Tried to select "custom" in "Use as" section and type /boot/efi manually, but it seems not to work.

Notice the warning icon, Is it unable to read because it is an EFI partition? Windows Bootloader on sda2 has the same warning . It is bad to have 2 EFI partitions?? Also, I know 2GB is a lot for EFI partition but... just desperate trying to do something different and I've watched some tutorials where that size is used specially on pop os!...

Here my lsblk:

NAME         SIZE FSTYPE   MOUNTPOINT
loop0        2.5G squashfs /rofs
sda        223.6G          
├─sda1       499M ntfs     
├─sda2       100M vfat     
├─sda3     114.2G ntfs     
├─sda4         2G ext4     
├─sda5      95.7G ext4     
└─sda6        11G swap     
sdb         14.5G          //Live USB using Ventoy
├─sdb1      14.4G exfat    
│ └─ventoy   2.8G          /media/pop-os/Pop_OS 22.04 amd64 Intel
└─sdb2        32M iso9660  /media/pop-os/Pop_OS 22.04 amd64 Intel
sdc            0B 

An here the last part of the logs where the installation always fails (complete log file is on a google drive link at the end). It seems to fail on grub installation step, and why is trying to install in BIOS mode? my PC has UEFI.

[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "kernelstub" "--esp-path" "/boot/efi" "--add-options" "quiet loglevel=0 systemd.show_status=false splash" "--loader" "--manage-only" "--force-update" "--verbose"
[WARN distinst:crates/chroot/src/command.rs:93] chroot: fallo al ejecutar la orden «kernelstub»: No existe el archivo o el directorio
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "update-grub"
[WARN distinst:crates/chroot/src/command.rs:93] Sourcing file `/etc/default/grub'
[WARN distinst:crates/chroot/src/command.rs:93] Sourcing file `/etc/default/grub.d/init-select.cfg'
[WARN distinst:crates/chroot/src/command.rs:93] Generating grub configuration file ...
[WARN distinst:crates/chroot/src/command.rs:93] Found linux image: /boot/vmlinuz-5.19.0-76051900-generic
[WARN distinst:crates/chroot/src/command.rs:93] Found initrd image: /boot/initrd.img-5.19.0-76051900-generic
[WARN distinst:crates/chroot/src/command.rs:93] done
[INFO distinst:src/installer/steps/configure/chroot_conf.rs:289] configuring keyboard layout
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "localectl" "set-x11-keymap" "es" "" ""
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "/usr/bin/env" "-i" "SYSTEMCTL_SKIP_REDIRECT=_" "openvt" "--" "sh" "/etc/init.d/console-setup.sh" "reload"
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "ln" "-s" "/etc/console-setup/cached_UTF-8_del.kmap.gz" "/etc/console-setup/cached.kmap.gz"
[INFO distinst:src/installer/steps/configure/chroot_conf.rs:277] re-enabling update-initramfs
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "sh" "-c" "rm /usr/sbin/update-initramfs"
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "sh" "-c" "mv /usr/sbin/update-initramfs.bak /usr/sbin/update-initramfs"
[INFO distinst:src/installer/state.rs:33] starting configuring bootloader step
[INFO distinst:src/installer/steps/bootloader.rs:35] /dev/sda: installing bootloader for Bios
[INFO distinst:crates/chroot/src/command.rs:103] running "chroot" "/tmp/distinst.vZLr2nxp1R5g" "grub-install" "--recheck" "--target=i386-pc" "/dev/sda"
[WARN distinst:crates/chroot/src/command.rs:93] Instalando para plataforma i386-pc.
[WARN distinst:crates/chroot/src/command.rs:93] grub-install: aviso: esta etiqueta de partición GPT no contiene ninguna Partición de 
Arranque BIOS; el embebido no será posible.
[WARN distinst:crates/chroot/src/command.rs:93] grub-install: aviso: El embebido no es posible.  GRUB podrá ser instalado con esta
 configuración únicamente usando listas de bloques.  No obstante, las listas de bloques son INSEGURAS y su uso está desaconsejado..
[WARN distinst:crates/chroot/src/command.rs:93] grub-install: error: no se procederá con las listas de bloques.
[ERROR distinst:src/installer/state.rs:37] configuring bootloader error: command failed with exit status: exit status: 1
[ERROR distinst:src/installer/mod.rs:300] errored while installing system: command failed with exit status: exit status: 1
[INFO distinst:ffi/src/installer.rs:190] Install error: command failed with exit status: exit status: 1

Complete logs: https://drive.google.com/file/d/162WdYhL4S9CNMZDtvBt8MmM4jstlNpeK/view?usp=sharing

Sorry for the question size but I tried to provide all the data I have and now at this point it is a personal matter between me and pop os. Thank you for your attention.

Hardware:

• Motherboard Ticnova e70 SFF (has ASRock UEFI)
• Ryzen 5 2600
• 16 GB RAM
• KINGSTON 240 GB SSD
• Nvidia GF 710 Series

Answer 1

This is the hint in your logfile:

[WARN distinst:crates/chroot/src/command.rs:93] Instalando para plataforma i386-pc.
[WARN distinst:crates/chroot/src/command.rs:93] grub-install: aviso: esta etiqueta de partición GPT no contiene ninguna Partición de 
Arranque BIOS; el embebido no será posible.

Translated:

Installing for i386-pc platform.
grub-install: warning: this GPT partition label does not contain any GPT partitions.
BIOS boot; embedding will not be possible.

It means you were booting the installer in BIOS mode and trying to partition the disk for UEFI. The installer tried to install GRUB i386-pc and failed.

Change the boot order in your BIOS and disable legacy boot if necessary. On some motherboards the boot option to /efi/boot/grubx64.efi needs to be added manually if it is not detected. See iso boot problem with UEFI on 20.04.

Since you already have an existing ESP (/dev/sda2), you should reuse it. Creating more than one ESP is not recommended.

You were also trying to create a FAT /boot partition which is not the same as the EFI System Partition. The ESP is only mounted inside /boot as /boot/efi.