We can use notes BUT, please pay attention to this. Github sometimes do things we don't like, one of them is how they implemented notes/warnings/callouts whatosever in their markdown viewer.
Instead of using common language of
::: info This is a cool info :::
They use:
Note
This is how Github want you to right a note in Markdown.
Anyway, we can use it, but need to follow Github convention here. Use the first won't render.