If I understand correctly, you already knew where to edit these features, but these modifications were not shown. Am I right?
It can be possible that your customizer preview is not working. To find out more about this, please click on the following link:
Note that you have the right reflex: you have to publish and refresh the page. The reason you can’t see the modifications after the refresh is related to the cache. If you’re on a mac, simply click on cmd + shift + r. It will refresh your page and empty the cache to make your modifications visible. Note that you can do it manually in your browser options.