I want to do speedruns on SM64 but i dont have time to do 70 stars and 16 stars is not posible. I can not find a catagory extontions tab for this game, if there is not please make one. Or can i just use the normal SM64 catagory extentions?

You can use switch in sm64 category extentions and there is runs(very little lol) played on switch https://www.speedrun.com/sm64memes/full_game also how about try emulator if you want run 16 star lol

Thanks, do you know any good emulater software, I'm unfamiliar with emulation.

more than 90% runner uses Project64 v1.6 (and 1.7+ is banned) https://goo.gl/PKGDn6 here is emulator setup guide I want to recommend good luck :)

thanks