I have no idea how to whitelist myself to get onto the server and I need an answer put in the simplest terms as if you're talking to a "slow" child.

Connect to your RCON > run the command: oxide.grant user YOURSTEAMID whitelist.allow

OR

Remove the whitelist plugin > connect to your server as "owner" > run the command: oxide grant user YOURSTEAMID whitelist.allow

OR run the command for allowing all admin: oxide.grant group admin whitelist.allow

I've just installed the mod and never touched mods before so everything you have said has just gone in one ear and straight out the other.

Where am I running the command? How do I run the command?

I need a step by step of how I'm supposed to do this.

I've provided you with a step by step in relation to this plugin. If you aren't familiar with using the admin tools provided by the server, I'd suggest searching for guides on using RCON in Rust and/or using the F1 console in game.
https://www.google.com/search?q=rust+rcon+setup