Hi, I’m struggling to create a custom class feature that adds magic missile to my Homebrew rangers spell list always prepared from level 3. Any advice offered would be great thanks. 

Rangers don’t “prepare” their spells, so it won’t work the same way as “always prepared” spells for those subclasses. Instead you need to add it as a “known” spell. Please see the Subclasses & Races FAQ #14: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).

Thanks. I had followed all the steps but it still wasn’t showing on the sheet. Toggling homebrew in the character settings fixed the issues. 

Ahh. General #5 then. Glad it worked.