My answer may not be the most popular or best answer and I’m sure, as there always is, someone is going to have some negative comment. But oh well, here’s my answer.
The best beginner printer is one that fits your budget, whatever you can afford. The prices range from $160. U.S. up to several thousand dollar desktop printers. I’m of the opinion that the best way to learn 3D printing is just as Edison did with the light bulb, make one. The ever famous or imfamous Anet A8 is a good place to start. It’s cheap, which is both good and bad. Bad because it come with potential hazards, although I have never in the 2.5 years of owning one had any issues. Good because you can learn from what makes it bad and improve it to make it better while making it a safer printer. While making these improvements, you will learn the parts of the printer, the differences between the various types of filaments, how to calibrate and level the bed, the different slicing softwares, and even learn to design with simple cad software, such as Tinkercad. The worse thing you can do with these such printers is learn something. There is plenty of sources online, and an equal amount of opinions. Deciding on what you want to accomplish with a 3d printer will help in determining the best printer to satisfy your needs. You may even find that 3d printing is not what you thought it to be. Rule of thumb, don’t break the bank for a simple interest. Start small and grow from there.
It’s a fun hobby and exciting hobby, after 2.5 years I have not lost interest and I have learned so much by doing and making.