Is it possible to add charges to custom abilities? I can't find a way. Is it possible to maybe use snippets in some way? I appreciate any help. 

You can set use limits for most abilities. It depends on what you are trying to do specifically.

I just want a way to track uses on abilities 

Then set the number of uses. I might be able to be more specific if you were more specific about whether it was an item, feat, race, subclass, or monster. "Abilities" is not a thing that can have a number of uses.

One is a custom action and one is a feat. 

how do you add charges to a racial ability?

Quote from TanGlubGlub >>

how do you add charges to a racial ability?

 
You don’t add “charges,” you add an Action with “Limited Uses.” Please see the Subclasses & Races FAQ #4 for a detailed explanation as to how to set that up: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).

I hope that helps.