Lower and side belly fats, so hard to get rid off 

Apaprently sit ups and stuff is to tone up your abs? In order to have visible abs, gotta do lost of cardio and fat burning workouts. 

I will recommend cardio or afterburn workouts ( mountain climbers, etc ) cause eventually we'll get bored of cardio 

If you have a huge layer of fat in front of your belly, by doing more abs work, your abs muscle will grow thus pushing the layer of fat further hence you will see that you are more fatter than before. Trust me, I've been there 

U cant do spot reducing. U can only reduce your whole body weight by doing cardio or weightlifting