Okay, so I tried going through the whole manual installation thing and got stuck on a specific file, receiving this message.
Failed to download file.
Name: labyrinthine.ogg
URL: https://resources.download.minecraft.net/b8/b83bbafa9799680da24f10215de2c40b73ce1fe3
Error details: transfer closed with 9074343 bytes remaining to read
Filename on disk: b83bbafa9799680da24f10215de2c40b73ce1fe3
Path: C:\Users\lemay\AppData\Roaming\.minecraft\assets\objects\b8\b83bbafa9799680da24f10215de2c40b73ce1fe3
Exists: Nonexistent
After downloading the file and putting it into the proper folder, it is deleted or moved when the launcher tries to access it, leading to the launcher stopping and the game not working properly. If anyone had this same problem and found a workaround, please let me know.
Solved it, if anyone else has this issue you need to go find the file somewhere not from Microsoft, download it, then put it into AppData\Roaming\.minecraft\assets\objects\b8\ and rename it as "b83bbafa9799680da24f10215de2c40b73ce1fe3", after that it should work and you can continue manually installing the other missing files.