This website I found by complete accident but has been a lifesaver in regards to finding good storybooks to read for the kids:
https://www.sonderbooks.com/Picture_Books/index.html
The website is regularly updated with tons of storybooks that you could use in class. While they are still books you have to purchase, it is nice being able to read the description, see the page count, and read a helpful review that mentions what the book covers in terms of topic. The "picture books" category in particular is extremely large and has them split into categories as you scroll down.
As the year is coming to a close, I feel the younger students really love putting their brains to work listening to you read these books for them and many, if not all of them, are available on Amazon and Kindle.
A little website with a lot of effort, care, and information put onto it for storybooks; and also a great leaping off point for those not knowing where to start when it comes to finding storybooks (such as myself haha!).
Also, if you are wanting to see the full contents of the books before you commit, going on YouTube and typing "X book Read Aloud" will usually pull up a video so you can see everything it has to offer the class.