How much can I do without buying anything with real money or having a subscription?

I recently was thinking about Star Wars, and I felt like playing a Star Wars game. I remembered about SWTOR and how it went F2P about a year ago. Although, I have heard that if you want to do any endgame, you need to have a subscription. I don't know the validity of this statement, but I wouldn't be surprised if it was true. I have also heard that there was a new max level, and you need to have a sub for that? Basically, I am just wondering how accessible is this game to free players?