A Real Best Friend is down to do whatever, as long as the two of you are hanging out together.
I’ve definitely had friends who would only hit me up if other plans fell through, or they just want someone to go out and party with. Your real best friend doesn’t care if you two just stay in, order pizza and watch Netflix all night. If you can’t enjoy just hanging out one on one, or find that when you do there are awkward silences, that person is probably just an acquaintance to you.