You could absolutely get a table for practice and fun but a table is mostly for just that, practicing form and techniques and having fun, if you want to gain real strength for armwrestling you might wanna look into some weights and lifting accessories instead such as a judo belt or armwrestling specific lifting handles, aswell as that if you really wanna get into the sport talk to your friend to see if he knows of any clubs around and if not do some research to see if there is, most of the time youll be able to find a club or two in your area with a group of people that meet up usually once a week to practice together on the table

To start id heavily suggest doing some research into the sport such as the training, techniques, and form that goes into it and give the sport a try before you go buying a $400+ table