Can you place a bet? I just grabbed one of the first articles when I googled it and:

“In-person betting will go live on January 31st barring any unforeseen setbacks. According to Joe Murray, there will be a “soft-open” on Monday, January 30th. This comes after the Massachusetts Gaming Commission approving retail licenses to Encore Boston Harbor, Plainridge Park Casino and MGM Springfield in recent weeks.

As for mobile bets, regulators have said in the past they hope to have mobile bets up and running in early March 2023.”

From a sports hub article but I’ve seen it on other sites:

https://985thesportshub.com/listicle/sports-betting-in-massachusetts-what-you-need-to-know/