as someone studying a nutrition degree, please try not to cut out certain foods or follow restrictive diet :,( it is not good and can affect your physical and mental health.
i assume you're speaking about losing fat, not just losing weight. one can be 54kg, have more muscle tone & be physically toned and the other can be 50kg have more fat tissue......
There are a lot of factors that go into losing weight to be honest. cutting food out or drastically restricting food can cause issues for your health in the future and you will regain it back. Try find the balance that works works for you. balance your meals as best you can with more protein to keep you from loosing muscle, drink water, cutting out......
Since some people are already saying tips, what you should NOT do is starve yourself. Don't ever do that. It is not the way! Please eat ofc with calorie deficit or wtv but NEVER starve yourself or eat unhealthy things. This is coming from someone who used to be plus sized.