Those are recent features. Are you using the current version of Adobe Animate CC?
I am using "Adobe Flash CC 2015"
aha! Just started the update to animate CC- thank you!!
The online help covers all versions, and so some features described are not in the application any more, and some will be too new to be in your version.
You can see here that the brush library and new paint brush tool came in Animate, during February:
Is there a reason you can't update to Animate?