I suspect you're remembering more than you realize. If you're talking about remembering names and dates - those sorts of specifics - that can be tough for any beginner. And everyone learns differently, so figuring out how you learn is part of the educational process.

I doubt that you're "not that smart" and that you're "not that bright" - so please put that crap aside. Everyone has gifts, and everyone has challenges. You're young and exploring, and I realize that obstacles can seem insurmountable, but if you persevere things can start coming together. I have a fairly profound learning disability, but I found how to turn it into a strength: remember, everyone has gifts!!!

The problem with memorizing events when you're starting is that the first few names and dates tend to hang there without context. It is much easier to remember the date of the 1000th event than the first ten. Context can be everything, but again, learning how you learn is key, and I can't tell you how it will all come together for you.

I can tell you that real history is not about memorizing the names and dates. It is about understanding the period and also the process of writing history (and reading what others have written). That, unfortunately, does pass exams, which at the early stage of learning tends to focus on the names and dates!

I'm not sure what to tell you without working with you and understanding how your mind absorbs information, but generically, I would say that the best thing you can do is to keep reading, watch good YouTube videos on the subjects, and try to absorb as much as possible - understanding the flow of events more than memorizing the specifics. You might find that if you understand a period in the past, it is easier to hang specific dates on that larger structure that you now comprehend.

Best of luck to you!