template will not apply an CSS

Hello, new here.  I've been playing around with the template designing my site to replace one on another host.  My issue is I can not get ANY CSS codes to work.  Is there some setting I an missing or something I need to change a setting in?  Super confusing and frustrating

Two things come to mind.

Are you creating CSS based on your knowledge of CSS for your site or are you trying to use code you found on the internet? If the later are you sure the code is for your SS version, template, and use case?

Are you putting the CSS in the right location and format? You can put straight into Website > Website Tools > Custom CSS. Other places you need to use a style tag.

Let us know how it goes.