You can use the gsettings command to modify the scaling-factor setting in the org.gnome.desktop.interface schema.
# Set the scaling factor to 2.5 (250%)
gsettings set org.gnome.desktop.interface scaling-factor 2.5
If you want to set the scaling factor for all users, you can use the dconf command instead of gsettings. For example:
# Set the scaling factor to 2.5 (250%) for all users
dconf write /org/gnome/desktop/interface/scaling-factor 2.5
Note that you may need to log out and log back in for the changes to take effect.
Alternatively, you can use the xrandr command to set the scaling factor manually. For example:
# Set the scaling factor to 2.5 (250%) for the eDP1 display
xrandr --output eDP1 --scale 2.5x2.5