If you have a gym near you offering boxing classes, then I would suggest you stop in there and check it out. Most gyms will allow you to take at least one free class before signing up to see if you like it. Or they might have a special promotion price. For example there is a Jabz Boxing near me and they offer something like 3 classes for $3, but you have to use the 3 classes within a week.
Unfortunately my gym doesnt have boxing classes i have to go in a specific place where it is only for boxing and it is expensive
The answer to your questions: You’ll never know unless you go into the gym and try it. It’s something that you want to do, so I think you should change it from a dream to a reality.
As a fencer I suggest fencing. Any type would do. Boxing can easily bring head issues. You won't get any serious injuries in fencing because of protective gears. It's quite expensive to buy some, though... Still, worth it.
It is not so expensive, just buy couple of cheap paper boxes and you can immediately start boxing and unboxing your stuff. It's good. Worth the money. It keeps you organized.