Elllzzzbelllzzz The black screen is normal. What is not normal is that the game gets stuck there instead of loading properly. And yes, this could be due to bad cc, which can stick to saved sims or households as well as existing on its own.
For .package files, you can use the 50/50 method to find the broken content:
https://modthesims.info/wiki.php?title=Game_Help:Finding_Problem_Custom_Content#The_50.25_Method
You may well have more than one bad item, so be sure to test each half rather than clearing it because you found the problem file in the other half.
For launcher-installed cc, if you're working with old .dbc files, you can use Method by Mell on this page to test them individually, and hopefully remove what's broken:
https://sims3.crinrict.com/en/2011/01/tutorial-how-to-get-rid-of-unwanted-custom-content.html
If you're installing .Sims3Packs fresh, there's no substitute for testing them individually. Do so in a clean folder each time, and set aside the ones that work for later use once you've tested everything.
The fact that this is such an involved project is an excellent argument for only installing what you're going to use now, or soon. You can create multiple Sims 3 user folders if you play with different themes, for example a Medieval or fantasy folder with only that cc, and a different folder for "normal" play with regular items. Just rename the folder you're not using and change the other one's name back to "The Sims 3" so the game reads the one you want. I have about a dozen such folders on my gaming computer, and several more on my laptop for testing purposes.