There are a lot of ways to jump into a group and have fun. You can find someone who knows what their doing and ask them to teach you. Depending on the game there are tedious steps in the process of doing basically anything, you can learn those steps and do it for them, like hauling resources or organizing items. You can find a niece to fill. Like for me, I love fishing minigames. A lot of people find it boring. So when I start a new game I usually fish if it's available. That way I contribute food and whatever else you can fish up.

Edit: I didn't see that this was Factorio specifically, but in general I think the advice stands.