Xcode crash

Welcome to the forum.

Your post is missing useful information. Please explain:

whenever I hit run or stop

So, if you hit stop, that means that you were able to run first…

• which version of Xcode ?
• UIKit or SwiftUI ?
• On device or simulator ?
• which version of MacOS ?
• Do you get an error message or a crash log ?
• does it occur with all apps ? If so, you should reinstall Xcode.