That’s great! Best time to learn is now.
If you want a textbook then Sutton and Barto (Sutton & Barto Book: Reinforcement Learning: An Introduction) is the typical textbook. The original version was written a while ago, so most of the book goes over the very fundamentals, but the 2nd edition does cover some deep learning, but it’s not the focys. It’s really good for learning the language of RL and how to think about it. You can jump around the book to see what interests you, or just get a feel for the fundamentals.
I personally think Julia is more suitable than Python or C++ for RL, especially as a beginner.
If you want to start experimenting, jump into the ReinforcementLearning.jl docs (Home · ReinforcementLearning.jl) and just start running examples and experiment with it. I always find doing things practically helps me learn more. The docs have a few tutorials and guides (start from Tutorial · ReinforcementLearning.jl). You can try and create your own environment or game and apply the different algorithms and experiment with different rewards. It’s all good practice.