Contrary to other three factions in Fallout 4 which requires grinding in some capacity, the Minutemen faction accepts with your arms wide open right from the moment your step out of Vault 111 to see what the world has come to.
How to Join Minutemen Faction
In order to join Minutemen Faction, all you need to do is to continue along the road from the Sanctuary and head southeast until you come to a place named township of Concord.
Once you get there, you need to reach the Museum of Freedom and begin optional missions offered by the Minutemen.
Unlike other three factions in the game, the best thing that I like about the Minutemen faction is that it does not concern them if you complete quests for other factions, but not in all cases.
Not to worry, though, as the faction will blatantly remind you if you cross any lines.
This is all you need to know in order to understand how to join the Minutemen faction. If there is something else you would like to know, make sure to let us know in the comments section below!