I am getting married after 3months need your help wanna lose weight?

i am 5.4 and my weight is 75kg so i want to loss 10 to 15 kg in 3 months .i go to gym regularly and do walking for 45mins and i started avoiding jung foods and oily foods etc plz plz help me out in this issue and one thing more is it possible for me to los 10 to 15 kg in 3 months? if not then how much i can do it?