I've lost 30kg since July. I have been on WLI which have honestly been life changing. I know some find them controversial, but it's not "cheating" - for me, it just levelled the playing field so the hard work I have been putting in actually shows results.
Absolutely follow CICO (calories in, calories out) and use a TDEE calculator to work out exactly what your calorie allowance should be.
Half your plate should be high volume low calorie foods, fruit, veg, protein. I find very low carb effective.
Working out will help build muscle tone, and of course burn some calories: but as the saying goes, abs are made in the kitchen. Exercise will only help, not allow you to eat and drink anything you want.
Download an app like MyFitnessPal or Nutracheck (I use Nutracheck) and you need to weigh and log EVERYTHING: not just the foods, but any cooking oils, dressings, sauces, seasonings. Some are far more fattening than you'd believe. Weigh your foods to ensure you're not underestimating calories.
If you're serious about losing weight you'll need to ensure you're aware of everything: a bottle of wine is great at the time, but as a PP said, highly calorific and some contain an astonishing amount of sugar.