Getting comfortable in a new enviorment, starting conversations and becoming fluent?

Getting comfortable in a new enviorment, starting conversations and becoming fluent? Hi, I am a male (16) 2 months ago I started at a new school, a boarding school. I live in the school, with a roommate which whom I can't speak with. I have trouble starting conversations, not just with him but also everyone, I wouldn't say I am scared of starting conversations, I just can't get myself to it, the best way I can explain this is, I imagine myself starting the conversation but I just can't get the words out I want, I feel like my brain just blocks me from doing it, I feel like there is a lock on my tongue, I want to get the key to this lock I imagine, I want to learn the ability to start conversations. I have only gone to this school for 2 months, I already made a lot of friends, and they are all supportive, I got 2 guys from my hometown which makes me feel more comfortable, they are very social and always try to help me by pulling me into the conversations with other people. I would describe myself as a very confident guy, I never ever let my stutter get to me, I have always been confident about it. I am social, I think I just need a kickstart, to get a conversation started, forexample when my friends are with me and they start a conversation, otherwise I am not very fluent in my speech, or comfortable starting a conversation. And if you don't mind me asking, what helped you through getting comfortable to start conversations, and become fluent in your speech, do you have any tips for "lowering" your stutter?