I recently lost 15lbs as part of a body recomp. My best advice would be first to make whole foods 90-100% of your diet if you can, with the odd day where you treat yourself.
Secondly as Pepsi said it's calories in and calories out, you can get a tracker or write down the calories of what you normally eat and with practice you get a rough estimate without thinking about it. This gives you a good estimate of what you might be aiming for to lose weight.
https://tdeecalculator.net/
Thirdly, drinking lots of water, eating slow release energy food like mono saturated fats eg. Eggs, avocado will satiate you without spiking insulin. Complex carbs might be good too but I'm not a nutritionist or a doctor. Natural yogurt, yakult and kefir with fruit is also good for your gut and it'll help digestion.
Either way, keep your diet simple and enjoyable, and I wish you the best of luck 🤞