These YouTube channels are perfect for learning new phrases and clarifying grammar concepts. They're also a great way to learn about the cultures of Els Països Catalans. As they're spoken in Catalan, they're useful for immersion, but do be sure to immerse in other materials - as these videos are usually spoken at a slower pace than normal conversation.

Català al Natural

Channel : https://www.youtube.com/channel/UCAUs47G3wtvo94GA0d7aauA

Tour amb Cotxe per Barcelona : https://www.youtube.com/watch?v=8HGpg3-eVGQ

Búnquer de la Guerra Civil a la Costa Brava : https://www.youtube.com/watch?v=GdD9Nr16gLo

Easy Catalan

Channel : https://www.youtube.com/c/EasyCatalan

How Does Valencian Sound? : https://www.youtube.com/watch?v=F9SedpzIRYg

Top 5 Best Catalan Films : https://www.youtube.com/watch?v=8HuUFHNiOcQ

Easy Catalan Podcast : https://www.easycatalan.fm

Dra. Aina Monferrer

https://www.youtube.com/c/AinaMonferrerPalmer

Plataforma per la llengua

https://www.youtube.com/c/PlataformaxLlengua

Institut d'Estudis Catalans

https://www.youtube.com/user/comunicacioiec

Learn Catalan from Barcelona

https://www.youtube.com/channel/UCsXMvYyUI9YVD344oHHDr7w

If you're interested in learning Catalan, there's a How to Learn Languages guide :

How to Learn Catalan