At your level in table tennis, fitness might not seem very important. However, if you want to improve 2-3 levels, fitness will become an important aspect of your game. Prepare for improvement! Avoid injuries! Increase your speed! Boost your endurance! At the end of every training session, do 20-30 minutes of intense physical training focusing mainly on foot speed, core strength, stability, and balance.
I thought about making a video with the 10-15 exercises that I do on a daily basis. However, I ran across this awesome video including some of the exercises that I do plus many additional ones. Start with the easy ones in this video then build up to the difficult ones.
Learn 44 New Exercises that will BOOST your table tennis game!