How long will it take to lose 30 pounds if I don't eat red meat and walk 2 miles everyday?

GOOD GOAL >15 weeks. Many studies show that a reasonable rate of weight loss is 1-2 pounds per week. So @ that rate 30# loss should take approx. 15+ weeks. You may have to look closely at calorie intake and 'not just stop red meat'. Perhaps a 1300-1500 kcal/day 'meal plan' will net you the weight loss you desire. It is a great idea to 'walk 2 miles a day'. Good job!