Referencing two spreadsheets (or tabs) on same app screen

Hi! I run into this so often, I assume it’s been addressed somewhere, but couldn’t find it. I’m doing a meditation/devotional app and on a certain screen I have data pulled in from the current day’s row from a spreadsheet (tab) of days. But on the same app screen, I’d like to pull in data (like a personalized journal) based on the User Data spreadsheet (tab). Is there a way using a relation column or something? I haven’t had luck with it yet. Thanks!