Just hit level 30 - very nervous for ranked

I just hit lvl 30 in league - I’m lvl 6 with Miss Fortune and 2 marks of mastery with her. So she’s who I’d main ranked games. I’m in silver right now.

I’m terrified of actually doing the ranked games because I’m afraid of sucking and ruining someone’s rank. Are there any tips for getting into ranked when you’ve been doing draft pick for so long now?

How do you deal with people being mean or fear of failure. And how the hell do you get out of silver I want to get to gold!!