Depends a lot on your personality; some people are successful with dramatic dietary shifts - I had success just straight switching to keto 7ish years ago, and it helped me drop 42kg over ~18 months. But I know for others such a drastic shift can be too over-whelming and smaller changes snowballing over time have worked better.

I’m pointing this out to begin with, because that there is no one-size-fits-all solution; everyone’s path is going to be a little bit different - and it comes down to your individual relationship with food.

Weight loss is ultimately all about one thing; a caloric deficit. Work out what your Total Daily Energy Expenditure is (there are heaps of calculators online), start tracking your calories using an app like MyFitnessPal or Cronometer (at least initially, until you get a feel for it), and find a way to comfortably, sustainably maintain a caloric deficit.

Exercise is a great booster, but you can’t put-exercise a bad diet. Focus on the food first, and slowly add in exercise gradually over time. Walks are a great way to get some sunshine, fresh air, and catch up on your favourite podcasts or audiobooks.