Enabling WiFi won’t help you connect to 127.0.0.1. That’s an address on your local computer. Ubuntu will generally download every package before starting the upgrade, so if it fails to boot, the packages are already on your system.

To get internet, your best option may be to hook your phone up to your computer through USB and enabling tethering mode. If your phone is connected to the WiFi, it’ll just become a WiFi dongle for your computer. Many WiFi cards built into computers require firmware that’s not necessarily available in initramfs, but the USB ethernet drivers generally are.

If you don’t have a phone with tethering support, you could try to manually start wpa-supplicant, if-up the interface and cross your fingers, but that’s more trouble than it’s worth in my opinion.

If you have enabled snapshots through something like Snapper or Timeshift, I’d recommend switching back to the last snapshot before the upgrade attempt and trying again.

If you don’t, I recommend either doing a clean install (copying over your home directory and any other user-modified directories) or booting a live installer, setting up a chroot, and trying to fix the issue from there.

The best way to fix broken upgrades is probably to remove all packages from non-Ubuntu sources (PPAs and such) and then try to apt install -t + apt upgrade + apt dist-upgrade until all packages are installed. You can try to reinstall the broken PPA packages again after that, but there’s a good chance you’ll break your system again.

I get the feeling the RDP package you removed wasn’t actually the one that broke everything (in my experience, this generally happens when another package sharing dependencies with it from a non-Ubuntu source caused a library conflict).