I’m 5’9 as well. I started out at 298.8lbs and I was able to lose all of the weight and I’m currently at 158lbs (a little over 500 days of IF and OMAD). I just want to say that you can definitely do this!
Biggest thing I did was calorie restrict. I started out giving myself 1810 calories per day which was a MyFitnessPal recommendation. Looking back now I would have given myself more calories and just slowly dialed them back. So my advice would be to track all calories as best as you can however give yourself a good amount because you can always tweak it.
I didn’t start working out until almost 200 days in to this but I’m now doing cardio everyday (peloton bike mostly) and weight training every other day (mostly dumbbell workouts) all from home.
I would say diet is 90% of the weight loss process so figure that out first.
I track everything in excel in order to know where I am having issues and what tweaks need to be made. I get most of this data through my smart watch but honestly these are things you do not need to worry about at first. Get in to a groove with tracking calories, give yourself some cheat days if needed but never turn it in to a binge or a cheat weekend or week. It’s all about making small steps over a long period of time.
Sorry for going on and on but feel free to ask any questions.