Like the other posts say, it greatly depends on what your starting point is and diet is essential. You can't put a time frame on it because everyone's body varies at the rate fat is burned and muscle is built. Once you lay down a proper foundation of diet, you can do various exercises that target the abdominal muscles. For us women who have had children, you may find that the rectus abdominus is lax. Meaning that they have separated during pregnancy, but you can still build and firm the muscle but may notice a separation--a split--down the middle of the abdomen. You can do crunches, planks, donkey kickbacks,
Body weight squats, knee raises, various yoga poses, the list goes on and on...
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