Tried to download on Microsoft Edge and Opera. Would try on other browsers but can't download anything at all.

So the issue is not just a Firefox issue, but more of Windows issue? What security software are you running? So are you a online, but just cannot download? Are you getting any kind of error message(s)?

What security software do you have?

It is possible that (anti-virus) security software is causing the problem. Try to disable security software temporarily to see if that makes a difference.

What keyboard layout are you using in case you selected a layout that remaps some keys ?

Boot the computer in Windows Safe Mode with network support to see if that has effect.

• https://www.bleepingcomputer.com/tuto.../how-to-start-windows-in-safe-mode/
• https://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10/