I would start with telling him how you feel and seeing how he reacts. Part of a healthy relationship is having things you do together and separate. I wouldn’t play fortnite if you don’t like it or at least not everytime. That might help him understand the feeling.

How long have you been together? Also early 20’s is definitely a time were people are still discovering who they are. It can be a self focused time too before adult responsibility sets in.

Does anyone know what other cities are building similar networks? Or how to get started doing it in your city?

It depends on how old you were when you were a kid and now. I would recommend getting your vaccination history and discussing it with your doctor. The vaccines do wane in effectiveness over time.