How to lose weight and gain more core strength?

Im 5’5 and about 138lbs. I’m really bad at dieting and I have a limited amount of food I actually enjoy eating (like I don’t eat fish and I do not eat steak but will eat chicken and LOTS of fruits and vegetables + a bunch of other things) I do stretches daily cause that is just what I ended up sticking to but I want to incorporate more core elements into my workouts .

In the summer I lost a bunch of weight and was like 125lbs but this was from not eating, don’t recommend 😓 and I gained it back anyways so..

That isn’t the point really but anyways I need some recommendations like exercises and foods that can
Make me lose weight, like 8-10 ish pounds but idk if that’s unrealistic

Let me know your stories!!