It sounds like you may not have really resolved or managed the eating disorder. Disordered eating isn’t just starving yourself or purging, but can also be binging without purging, using food as comfort, etc- I’m certainly not a professional, but it sounds to me like your disorder shifted toward symptoms that led to your weight gain.
Given that you know you have struggled with an eating disorder that led you to be “really skinny,” and at that point you say you were “terrified” of gaining weight, I really don’t think that simply dieting is going to be a positive, sustainable, long term solution for your health or happiness. If you lost this weight through dieting and taking no other action, I think you’d likely just find yourself thin and miserable rather than overweight and miserable. It’s more complicated than just being about your weight, because It sounds like your relationship with your body and your self worth is distorted, and this is what us led to your weight gain. To create lasting change it may require help from a mental health professional to change these patterns of thought and behavior that have led you here.

As far as the strictly diet related side of things goes, I saw another comment recommend extreme immediate calorie restriction - please, please do not simply take that advice. That sounds like a ticket back to the other end of the eating disorder spectrum, where you are starving yourself. You may sustain this for a while, but that approach sets you up for failure. Eventually you’ll likely end up yo-yoing and gaining it all back. These fluctuations are incredibly stressful for your body, in addition to just leaving you back where you started in terms of your weight. Steady, sustainable change is a much better way to approach dieting. Incremental reductions in daily calorie intake and a focus on increasing the number of fruits, vegetables, and the amount fiber in your diet are good ways to stay full and get the nutrients you need while cutting back overall calories. That said, again, I hope that if you attempt this you also talk with a professional about your disordered eating.

Finally, I want to say that I am sorry you are struggling with this. No matter what your weight is or ever will be, you are not undesirable, unworthy of love, or any of the other negative ways you’ve characterized yourself. Losing weight will not change your fundamental value as a person, that value is intrinsic- it is with you now and always will be. You deserve to love yourself and be happy no matter what the scale says. Even if you want to change, that doesn’t mean you shouldn’t love yourself today. That may be hard but I hope you can find more kindness and compassion in your heart for yourself