What are the best resource hubs for accessible undergraduate Micro and Macro materials for non-economics majors?

Sorry if I am in the wrong sub, but I don't know where to ask.

I’m looking for reliable “resource centres” (websites or repositories) with teaching and learning materials in Economics (both Microand Macro) aimed at undergraduate students whose degree programmes are not primarily economics.

Because these students are not specialising in the subject, the materials need to be clear, applied, and not overly technical; otherwise they tend to lose motivation and disengage.

Thank you in advance for any recommendations (even if the right /sub)! 🙂