Edit: In order to protect your privacy and security you need to understand how the tools you use work and what purpose they serve. There is no "app" that will do this for you. There are plenty that promise this though, and unfortunately this causes many people to assume there's no attainable security. They see news articles saying a supposedly secure app was hacked, and without understanding the circumstances that leads to the outcome, post comments on threads like these claiming there is no way to be secure while using the internet.
My original post: Start by understanding what Tor and onion routing do in general, especially compared to a VPN. Read through this: https://support.torproject.org/about/ at the minimum. Also, understand that using these tools won't keep you safe or anonymous if your intention is to log into any of your existing accounts. The goal should be to separate what you want to do anonymously and make sure to not have any overlap with whatever your existing accounts are since those are already very much tied to you.
To actually use Tor I'd recommend starting with Tails: https://tails.net/about/index.en.html on a USB stick. If eventually you want to have a laptop or similar device that can persist some data maybe checkout Whonix: https://www.whonix.org/. The best setup would honestly be Qubes OS, but it's definitely not a good starting point for anyone not already familiar with unix-ish systems.
I'm assuming "Krusty Gets Busted". I literally just watched this episode for the first time less than an hour ago and this post is bugging me out.