Misc URL fixes and fix the Roblox page

[Ast3risk-ops]

Type

• [x] Rewrite already written documentation.
• [ ] Add/remove new pages.

Questions

• [x] Did you preview on your local machine beforehand?
• [x] Did you follow our commit handbook?
• [x] Did you read the Atlas Contribution Guidelines?
• [x] Did you commit to the dev branch and not master?

Describe your pull request

Fixed a bunch of broken URLs and page links and reformatted @trolljoe's work on the Roblox page.

[Ast3risk-ops]

also the list using 1s may seem weird, but the theme converts it into a proper numbered list, don't worry.

[Ast3risk-ops]

We may want to fast-track this to master as well, seeing as the roblox page is already there.