How to run adsense ads on Jetpack Mobile site

I have successfully added 1 adsense ad on my Jetpack mobile site on the bottom of my article content on a single post page by using the code provided by this website:

https://techjourney.net/how-to-insert-show-ads-google-adsense-in-jetpack-mobile-theme-of-wordpress/

This code seems to only allow ads to show up on the top or bottom of the article content on a single post page.

First, can someone provide me the code to place an ad at the very top of my website, and not right on top of my content because that separates my post title from the content which I don’t prefer.

Second, can someone provide me the code to place these ads on all my pages (front page, single post, archive, category) and not only the single post page.

I am a beginner, so an easy copy and paste code like the website above provided that I can put directly into the “edit functions” area of my site would be very helpful. Any help would be much appreciated. Thank you. The website is https://www.imaginarybrickwall.com