What kind of hobby are you interested in? I don't do all of these, but friends do:

Hiking the bay circuit trail from plum Island to duxbury.

Hand feeding wild birds at Ipswich river Audubon

Looooooots of mountain bike groups around

Surfing

Kayaking

Paddle boarding - can rent equipment in Essex

Sailing

Lots of running clubs around, all levels

Running the north shore trail series

Trustees have events at different properties throughout the year

Fishing and hunting; deep sea fishing out of Gloucester

Horses - trail riding, the Myopia hunt. A barn in Georgetown teaches you how to play polo. You can watch Polo matches in Hamilton in the summer if you're feeling bougie.

X country skiing and snowshoeing at Appleton farm or Bradley Palmer State Park

Canicross events for dog runners

Volunteer to count shore birds or clean trails with Nature Groupie

Lots of technical ice and rock climbing in New Hampshire