Customize the front page in toujours theme

Hi,

I am new in wordpress and I am trying to do the following:

1. move the tagline right under my site title instead of being under menu 1.

2. Add social media icons on the top right of my homepage

3. Add a “search” option on the top left of my homepage

4. Make the colour of my site title black.

I am using the toujours theme and the link to my profile is: https://valiapanousi.com/

Could you also please let me know, whether I should click the “Don’t use the theme’s original CSS” in order to make these changes.

Thank you very much!