How to remove stripped screw?

I’m working on this old scooter I got for really cheap and one of the screws seem to have some heat corrosion cause I couldn’t get it out for the life of me, I was trying for about 5 minutes and then I felt a snap and thought a cracked the seal for the screw but the fuckin thing stripped pretty bad. Winding if anyone has some tips to get it out. I’ve tried some tips online but they didn’t work well cause it’s stripped and tight in there