I wouldn't consider it a date unless the guy actually asked me out and made it obvious to me that it was a date. If I'm just hanging out with a friend and he offers to pay, it's still just two friends hanging out. Him offering to pay doesn't suddenly make it a date in my opinion.
Depends on the guy you're with. My best friend always tries to pay for everyone. It's normal to pay for a friend. Some other guys just hate girls paying. Depends on what type of person your friend is and if it's normal for him.
It's not a date... I think because chances are he was just acting like a gentle man would... #chivalry 😘 Unless he actually asked you out or at least, dropped off a hint or two, I don't think you should read more meaning into it