I am trying to add spell to the barbarian for a Subclass. But I don't know how to add spell slots to a class without spell slots. Can anyone help me find out how to add spell slots to the Subclass.

Sorry, I would have responded to your question sooner had I seen it. Next time post in the Homebrew forum and I’ll see it sooner.

For the answer to your question, please see the Homebrew Subclasses & Species FAQ #7: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).

Oh ok. I did not know that existed thanks for the help.

Happy to help.