Build a Website

I have a Shopify store and am looking for very minor tweaks made to the code on the theme I have. Normally I would do this myself but with everything else going on I don't have the time and I am under dead lines. I would like my navigation bar moved down on the screen to be closer to the navigation break line and I would like products shown on the home page sized so it is 4 across opposed to 3 across on the grid.