If i only eat healthy everyday & not work out but take walks 3 times a week, how long will it take to get my cholesterol lowered on blood work?

It depends: Eating healthy and regular exercise are essential for lower cholesterol but it is hard to quantify the relationship. Usually thee is likely to be significant change in 3 months. Best to check with your doctor if you also need cholesterol lowering medications

Variable.: Your on the right track, but there's no specific timeline for your efforts to take effect. The key is to stick with it in the long term.