mummas with toddlers

I have a 3 year old son and I'm somewhat happy with my body but my partner and I have been talking about getting engaged so I wanna work out more just to lose the extra few kilos. But finding it hard because I'm a full time mumma. I'm wondering what are some good exercise routines you do at home. I just wanna tone up my belly area, lose a little weight in my thighs and tone up my butt :)