If you're a truecel, it's only worth it for health reasons. If goyslop is a large part of what keeps the gun out of your hands, so to speak, I wouldn't be so quick to give it up.
All you have to do is consume less calories than you currently do. Just keep in mind that it's not recommended to go down more than 1 kg per week, and going down 0.5 kg per week is the standard (but going down exactly 1 kg per week is also fine, *just don't go over that*). You can use a calculator like this to figure out the exact numbers for this stuff:
Use this calorie calculator to achieve and maintain your weight loss or weight gain goal within a realistic time frame. It calculates the daily calories and macros you need to reach your desired weight.
www.fatcalc.com
It will also give you an example of what a balanced diet would be in terms of protein, carbs and fat which you can follow if you want to. To make it easy for yourself I'd just look up whatever it is you want to eat each day, how many calories that is (and nutrients too if you want to), until you have reached your calorie intake for the day. If you get hungry you can always exercise a bit to burn some calories and then eat again (walking would be an easy exercise for most people). If you're weighing yourself during this process remember that your weight will fluctuate a lot during the day due to many different reasons, so you can generally only be confident about how far you have progressed every four weeks or so. It is also normal to lose more weight the first week than you will the following weeks.