There are a wide swath of options depending on your availability, desire, and preferances.
Executive Assistant - An addon that allows you to spend a undetermined amount of time setting your goals in bullet form that list on a drop down menu. Once you understand the addon. (Takes a bit).
You have the default D- Daily, W-Weekly, M-Monthly lockouts / goals.
There are options for per character goals and account goals. Every time you log on a new character a new list can show.
The downside to this is that it doesnt automatically remove or add items.
That said, its fun, enjoyable and a bit addicting to meet your goals.
Wordpad -Notepad - are my go to choices. Its an easily updatable and configurable choice. Copy pasting links from wowhead, fan sites, useful weak auras, w/e.
I lost interest with Executive Assistant for this choice years ago.
There is an updated version of Executive Assistant called, something. Im not home for the next week to check. Its great. You can link Achievements, out of game links too (I think). In your to do list.
Spreadsheets- if you are an Excel fan. Primo. You can do wonders with charts, stat tracking, colour schemes, ranges, hell. Sky is up.
Its far more time consuming.
AllTheThings Addon.
This addon at its basics, will load every item in the game and where there are looted from.
Every heading has a shift click for world locations for coordinates, map icons, (if you have TomTom enabled), a directional area where to go.
The same method works for quests. Breadcrumb locations. Rares.
There are extremely detailed footnotes when you hover over each item that details where, when, and how a thing is obtained. If its not clear.
Every lockout you complete will show you a checkmark next to raid if you completes it for the week. Per toon. Per difficulty
Lastly, Dataforazeroth.com will allow you to load your character / account profile from armory to show you world rankings. Click on any character will let you see individual tracking types.
Each type will show every missing / remaining item. With a direct link to wowhead and those lucrative comment sections.
There are also a variety of discords that update all the new content and all the things to do for completionists in so much raw glory.