can you take a train ride and stay at different lodges and go on bus from site to site? is there a tour leaving from MN and go for a week?

I took the Empire Builder from St Paul to east glacier and stayed at Glacier Park Lodge, the historic inn built by the railroad. The lodge sends bellcaps in costume to meet the train and carry you and luggage. There are bus tours and rental cars nearby, either could take you to other lodges.

Yes, you can take the train to East Glacier. There are several lodges where you can stay and there's a bus connecting them.