how do i know if my game is ready for a loading screen?

ive been having some scripting issues lately with some scripts not working so when do i know its ok to add a loadiing screen so scripts can load faster etc

Put this code at the beginning of your script:

game:GetService("ReplicatedFirst"):RemoveDefaultLoadingScreen

So that'll load quickly and replace the regular loading screen with that. Also add as little wait()s as possible unless it's necessary or for stylistic effect.

Usually people make it pop up at the beginning, So that every things loads so my answer to your question is: You should start your GUI at the start of the game and make it long depending on how big your game is