Before just outright deleting your account, be sure to edit all your posts and then delete them as Reddit only keeps the latest version of the post. There are scripts out there to automate that process, but I have found a quick and easy Chrome/Chromium extension that will also do the same thing.
Depending on your profile age (mine was 9 years) or total number of comments and posts, you'll likely have to refresh the page it opens after it says it's done deleting comments and posts. I had to perform a refresh in that way about a dozen times, but it eventually got everything.
Stay safe and cover your tracks, y'all! You never know what can be used against you later on.
Also, if you can, move to private Riot (https://riot.im/) server instead of using Discord and, as much as possible, use the Signal app for text messaging and Mumble (https://www.mumble.info/) for voice chat. The more people that do it, the more texts and voice chat will be encrypted.
EDIT: Music to listen to while nuking your account - https://www.youtube.com/watch?v=oaJQrfTo46Y
EDIT 2: Another user suggested to me PowerDeleteSuite - https://github.com/j0be/PowerDeleteSuite
Thanks.
This is all new to me. I appreciate your putting it in one place.