Bonding new kitty with existing kitty

My family has had a boy cat for almost 2 years now, and he is super playful so we thought he might like a friend. He is pretty aggressive when he is playing with us humans, lots of scratching and biting. We thought he would do well with another cat bc I was cat sitting for my friend about a year ago, and although there was some fighting initially, he got along with that kitty after a couple days (she was a female about his age).

We got him a friend almost 2 weeks ago. We have been keeping them separate, and trying to make them comfortable with eachother by having them eat beside eachother and have some nose touches. He will sit at the door meowing bc he wants to see her (she is kept in the master bedroom, he roams the house). When they are in the same room and are not restrained but us, there is no hissing or anything and she will try to come up to him to play. He plays back, but he is way too aggressive and I can’t tell if he would actually hurt her or not. There have been a few times where he has made her hiss, meow, and growl from attacking her.

It’s been 2 weeks and I’m not seeing any improvement. I don’t know what to do to get them to bond, or to even get him to stop completely jumping her. Please help!! I don’t want to have to give her away.