The newtonville train station should be open now. If you have a smart phone you should download the mticket app. Otherwise bring cash with you and buy it on the train.
You will be able to purchase tickets on the train. There is an app that you can download onto your smartphone to purchase MBTA commuter rail tickets. But, be wary, I believe that Newtonville Commuter Rail Station is being renovated, so you might have to go to West Newton's Commuter Rail Station to take the train.
Use the mticket app
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