Avoiding losing weight during Ramadan

You can eat once or twice a day right? So it's like IF?

Get your protein and eat till full.
Remember to continue working out to maintain muscle. Should only affect your fat and not muscle unless you eat junk.

Doing keto would make it easier as you would not feel as hungry.

You're going to have to go for calorie dense foods, while making sure you don't eat an excessive amount of sugar or sodium at suhoor. I'm trying to maintain while fasting and even that is hard. I've been eating 10% fat greek yoghourt, whole wheat bagels with a lot of cream cheese, higher calorie protein bars, avacados, tea with heavy cream, couple servings of cereal, oven roasted chicken thighs, protein shakes, unsalted nuts, nut butters...I have 5 dates at iftaar and that is easily over 100 calories. This is just some of the higher calorie things I've eaten, but you get the idea.