Hey. I have been living in Portsmouth for a while and have a few ideas.

I also have a 21yo son that just moved to Charleston SC but when he is home he enjoys going out to the Press Room to see some music and TJs but he says mostly college kids and not his thing anymore . He always winds up there though :)

If going out to bars isn’t your thing got some other options. Volunteer for the Music Hall . Just starting to do that. Mostly older people but good way to meet local folks and see some good movies and bands . The Portsmouth Makers Space is good if you want to make stuff and needs volunteers and PMAC is great to join and look for a way to get involved if you enjoy art. The Gundalow in the summer is a great way place to volunteer and get free river crusades. Have some friends that do that.

Jimmys Jazz also has volunteer slots I believe and very cool place.

Good luck. Feel free to DM if any follow up needed