MacBook Air full of unknown files

o have a macbook air and when i search on my mac and it searches on the "this mac" there is many weird files and i tried to delete from there then i realized some were kinda like codes? with apple license and i might've deleted some before realizing is that okay? or did i do something i shouldn't have done :| and what are these files? i want to get rid of them they are taking space is that okay?

[Re-Titled by Moderator]