Lighting and rendering are broad subjects with numerous ideas under their belts, so I'll point to some resources.
There are plenty of reputable artists and educational channels on YouTube that put up excellent instructive material. Marco Bucci published a series that condenses various fundamental painting skills into 10-minute videos; Stephen Bauman has a “drawing essentials” playlist composed of snippets from his lessons on Patreon; and Sycra has a 17-part series called “Foundations of Light and Shadow”.
However... If you can also invest in some books, I highly recommend it! When I’m learning about smth for the first time, I look for resources that do ideally two things: (1) answer my questions ASAP (and as accurately as possible) and (2) give me answers to questions I didn’t even know I had. For these reasons, I like books like Color and Light by James Gurney and Color & Light by 3DTotal Publishing precisely for their accessibility and breadth.
Gurney’s Color and Light is a very friendly resource, mainly for its language. Gurney uses simple syntax, and each chapter is chock-full of examples, practical insights, and delightful imagery, which can all help ground unfamiliar information into place. This resource is great bc Gurney surveys an array of topics, such as the anatomy of light and shadow, Munsell’s color system, types of light sources and scenarios, to name a few. One caveat is that Gurney writes with traditional media in mind, so if you’re looking for tips on digital tools, you won't find too many here. Nonetheless, the principles and phenomena covered in this work are relevant irrespective of which medium you use. Though, if you want digital-specific tips, I also enjoy Artists’ Master Series: Color & Light by 3DTotal Publishing.