Issue at Hand
You report that you have deleted
/etc/apt while attempting to delete your
sources.list file. Now you experience errors when attempting to use
I have referenced this post. Perhaps it can help you?
First, see if you still have a copy of
Now look for a
.deb with apt in its name, if you are running Debian Stretch on a 64-bit system it should be
apt_1.4.8_amd64.deb. Use tab to autocomplete, or if not found you can download
apt and its dependencies here.
After you have located the necessary package run as root(sudo) the following command:
dpkg -i apt_1.4.8_amd64.deb
This should reinstall the apt for you. You should now be able to run
sudo apt-get update && apt-get upgrade as expected. Remember if you need to recreate your
sources.list file you should follow this example.
The error about missing
/usr/lib/x86_64-linux-gnu/libapt-private.so.0.0 should be solved if not you can install the lib from here.
Then you need to copy the library file into /usr/lib and run this command as root(sudo):
ldconfig -n -v /usr/lib
This post may help too.
Please comment if you have any questions or issues with this answer. I highly suggest you read through each link I have provided thoroughly before attempting the commands. I appreciate feedback to correct any misconceptions and to improve my posts. I can update my answer as needed.
Best of Luck!