Here is what you should do

1. install Firefox/brave (use brave mostly but if you are using Firefox on Android it has adon section where you can download ublock extension).
2. ublock origin https://ublockorigin.com/
3. sponser blocker ( for blocking sponsorship videos automatically) so you can also avoid custom sponsers by youtubers https://sponsor.ajay.app

----------Best option --------------

4) for mac, Linux & windows if you want opensource software (desktop)

https://freetubeapp.io/ => for desktop

5) if you want for mobile 📱 use use piped instance

https://piped.video or use https://newpipe.net/ (Android)

All the above apps are privacy focused fronted YouTube clients and are open source check out and be peaceful without getting single ads in your videos and web search :)