Hello mate, congrats to have chosen to work on yourself!
What you're doing is good, but it's not enough in my opinion. Keep approaching a girl per day, but at the same time try to talk with anybody you can, and you don't have to come up with super interesting topics. Just say "hi, how are you?"
There are a lot of situation where we can say these easy words but we prefer to say nothing. For example if you're in the metro and you sit close or in front of someone else. Just say "Hi, how are you?", nothing else.
It doesn't matter if the other person will reply to you or not, the important thing is that you pushed yourself to do something that you preferred to not do.
If we want to get good with girls, we first have to get good with people in general.