Hanging out in a group is not as terrible as it seems, especially if you can make friends with at least one person in the group, either before you hang out, or while you are there
It is important to recognize that the group you join or want to talk to also have a certain level of etiquette. It is respectful to my mind to welcome a newcomer in a group and introduce them, perhaps fill you in on what they are talking about and that you feel welcome.
1. Start hanging out with one to three people to make a small group. Usually you will feel comfortable, especially if you are close to or more personal with them
2. When you become more familiar with your friends, branch out your group. Go on excursions and meet new people, you will notice that your group will grow larger. All you have to do is act in the same way as you did in the small group.
3. Bare branch out further. If you start to feel a bit awkward in a group of 6, and more so you just have to talk to the people individually. By doing this, you can be more personal with the extensions of the original group and meet new people at the same time.
4. Try a public speaking. It will give you greater confidence to speak in front of people. When you arrive in front of the small group of people you will find it easier after working the courage to give a speech or presentation.
After imagining all this, you know how to behave in that situation. Once you know how to behave, you feel comfortable enough to hang out. Do not forget to be cool and quiet.
I hope this helps.