You probably don’t need to dive into the start of the art, at least not immediately.
As such, standard machine learning libraries are a great place to start.
As such, I recommend starting with some experiments with scikit-learn:
You can practice on standard recommender system datasets if your own data is not yet accessible or available, or you just want to get the hang of things first.
Popular standard datasets for recommender systems include:
If you are ready for state-of-the-art techniques, a great place to start is “papers with code” that lists both academic papers and links to the source code for the methods described in the paper:
There are a number of proprietary and open-source libraries and services for recommender systems.
I recommend sticking with open-source Python libraries in the beginning, such as: