For one of our customers I had to create a solution with folders within a list. The challenge was to set a different view for the top document library view and the item in the folder view. I was having some issues with the configuration until I found the following post:
Jasper Oosterveld is a Microsoft MVP and Modern Workplace Consultant from InSpark within the Netherlands. On a daily basis, he works with customers to implement the Modern Workplace with Microsoft 365. Jasper focuses on collaboration, communication, security, adoption and governance. Jasper loves to share is expertise and love for Microsoft products with everyone who is willing to listen.