Can’t find the right way to lose weight..

Hello! A few years ago I got pregnant for the first unfortunately I lost my baby. Throughout these past years I have gained weight but lately i’ve gained so much(I’m not pregnant). I’ve never been this big. I am currently at 170lbs, mind you i am only 4’11 so you can tell i’m overweight. I do not like the way I look or feel. I feel so unhealthy. I was wondering if my body change from the time I was pregnant because it feels weird & I feel like I cannot get back to my body before pregnancy. I tell myself I’m delusional because I did not have the baby so how could it possibly have effected my body. I don’t know. Please help! I’m trying to lose some weight but I can’t even understand my own body.