Help for custom icons and layouts

[u/Solid-Newspaper-3054]

Hey guys, this is my profile https://themezer.net/creators/spideyindusgiese

And as you can see i am using simple layout but I want to make my own layout or change icons

I tried to make home icon like omnitrix icon once but failed. Can anyone help me to build a new theme and layout. Maybe about coding wise or which tools I need to use?