Sport should be an addiction, not a chore. It might be hard at the beginning, but you should do something you actually enjoy.
OP ,if you had your dream body, what do you picture yourself doing?
Start slow, but be consistent. Better 3 gentle exercise a week for 6 months to start, than going crazy every day for a week and give up!
Some people cannot exercise on their own, they can't find the motivation and they need a class of some kind. That's absolutely fine! Don't be ashamed or embarrassed to start - real sporty people are actually very supportive and never look down at someone even obese trying to join them.
Find whatever you like, ideally a combination, and stick to it for at least a year. You WILL hurt, you will be sore, but you will feel good. just don't go crazy, and enjoy zumba/netball/jogging/ tennis/ martial arts ,.... whatever it is you like.
3 hours.. just 3 hours in a WEEK, that's nothing is it?