I can’t think of a good tutorial but here’s the process in the nutshell
1. Create custom audiences in Google analytics based on actions/goals users do on your site or lack of them
i.e. on e-commerce website you’d maybe want to create an audience of users that have placed items in the cart, but didn’t finish checkout
Another example would be audience of people that did buy something in the certain period, so you create different ads for these two different groups.
These actions can be set up via events/goals and you implemented usually via Google Tag Manager, but different platforms might have plugins to make it easier for you.
2. After the audiences have been created, you import them into Google ads account
3. Use the audience you want while choosing targeting options during the ad campaign creation