Some problems with my first github/jekyll pages

Hello !

I’ve created my first static website with github pages and Jekyll. I use the Minima theme. I’ve 3 questions about this theme :

First question :

I want to change the order of my categories on my navigation bar. For the moment, I’ve this :
I would like :

Homepage  skill CV cc

But I don’t know how to do that…

Second question :

As you can see on the picture, I’ve created a file with the page layout :

layout: page 
title: skill 
permalink: /skill/

So this page appears in my navigation bar, but when I click on it, the title appears on the page

Can you tell me if it’s possible to not display this title ?

Last question :

I create this array :

Activities skill achievement
1 [My first activities] ({% post_url %}) 60%

I would like that when I click on the link, the post opens. This file is in

I think I need to put a plugin in the _config.yml because I have a github build page failure…

Can you show me how to do this ?