Random collection of thoughts, there is a pretty active FB group/Discord server that have a bunch of random activities

https://www.facebook.com/groups/3109143809154886

https://discord.gg/TSWJvEcA
Bike-specific groups that host rides in the warmer months

https://www.facebook.com/groups/500325783405970/

https://www.facebook.com/groups/325402935531296/

Meetup is also great for that

https://meetup.com/

Lastly there is a Boston specific subreddit

https://www.reddit.com/r/BostonSocialClub/

Freedom Trail is really a must as a Boston experience. Boston as a whole is still one of the most segregated communities, so I'd also be remiss if I didn't encourage you to visit and patronize the businesses in the "lesser traveled" areas; Dorchester, Roxbury, Mattapan (someone already mentioned Darryl's).

As mentioned JFK Museum is pretty nice, a bit further out but worth the trip. Of the other museums, Isabella Stewart Gardner gets my vote.

Castle Island (not actually an island) for a lovely walk by the water.

The Boston Harbor Islands (actual islands) are also great for a day-trip.

Not necessarily your fault OP, but housing should really not be looked at through an “investment” lens

Does the place you’re looking to live fit the needs of your family? Can you afford it?

Undertow Brass Band, I think they’re pretty selective though

Maybe The Party Band from Lowell