Front page issues

Hi all

I hope you can hope, my website is https://www.africanoverlanders.com/wp

I am really struggling to configure the front page, the rest of my site is getting pretty close to what I want but I have a few issues. I hope you can help.

The slider that is on the front page, how do I put pictures on it or how do I delete it if I want to use a different slider.

How do I get the writing below into the centre?

How do I get photos into the three boxes below the slider?

I am using the social icons widget how can I place this next to the search box at the top of the page on every page.

Any help greatly received.