is there any tutorial for beginners on how to use the things over here?

My first time here and I'm not sure I understand what I need to do to use the models here.

I would appreciate a short guide if there is one

Check her guides: https://civitai.com/user/theally/articles

I belive there will be enough info to get started.

Hi there! We have a Civitai Education Hub with a lot of good info - like the 100% Beginner's Guide

https://education.civitai.com/

official docs