OJS 3 how to present journals images at front page in rows with filtering option

I am novice in OJS and can’t find front page file structure dependencies description. I would like to customize front page to present all the journals in rows using their images with filtering option that should allow to select journals in selected departments.
Every suggestion is welcome.
best Regards
Zbyszek Ruszczyk
University of Gdansk

If you mean editing the site index page, then the template is here: https://github.com/pkp/ojs/blob/master/templates/frontend/pages/indexSite.tpl

For our site we created a custom site theme that includes a custom indexSite.tpl. See GitHub - ajnyga/tsvSite: Journal.fi site theme for OJS3 / tsvSite/indexSite.tpl at master · ajnyga/tsvSite · GitHub