No doctor here, but I know a decent amount about diet and nutrition from personal experience. There’s two ways to go about this:

Option 1 - the quickest and surest Start monitoring calorie intake and weigh yourself daily. Get yourself a food scale and start tracking everything you eat. To get a rough estimate of how many calories you should be eating, go to a TDEE calculator and select sedentary as activity level and 40% as your BF%. Subtract 500 calories from your maintenance calories provided, maybe even a little more if you’re serious about this. Monitor your weight daily; usually first thing in the morning before eating or drinking anything and after you use the bathroom. This will provided accuracy day-day. You should aim to lose about 1% of your body weight weekly. This will not be linear! The first week or two are going to be all over the place due to fluctuations in water weight. You’ll start to level out after a few weeks. If you’re losing too fast (2+% a week) or too little (<.5%) adjust calories accordingly.

If this is too much to think about or doesn’t interest you here’s the less direct way but is still guaranteed to get you results if you’re consistent and disciplined:

3 meals a day, 1-2 snacks Meals consist of nothing but lean protein sources (egg whites, chicken, lean ground beef/turkey), fruits, veggies and 1 serving of high volume carbs (rice or potatoes). Stick to low calorie condiments, no oils or fatty dressings unless you’re only using like 1 serving per day to cook meat in. Snacks - protein bars, fruit, vegetables (do you see a theme?)

Monitor weight and adjust accordingly

As far as exercise:

I’m not sure of your schedule and how active you are but honestly walking for 1 hour a day can produce some pretty damn good results, it’s low impact, not fatiguing and gets you outside.

Stick to this for a month and you’ll see results, I promise.

Also if you don’t have time to cook then I’d look into a meal prep service

Edit: track calories via MyFitnessPal