How do I update OS X El Capitan Version 10.11.6 to Mojave?

I own a 2015 Mac Book Air and I have recently made the mistake of upgrading my Mac OS to Big Sur, after using the newest version for only a week and realizing the pain of not being able to run 32-bit applications I used a time machine back up to return my OS to El Capitan and I would love if I could update it to the Mojave version and NOT Big Sur or Catalina. If you could help me with my problem that would be greatly appreciated. In the five years I have owned this thing nothing has brought me more distaste for Apple than the two newest versions.