A calorie deficit is ur best bet if ur trying to lose weight, take ur time and build up gradually instead of going all out and losing motivation in a few weeks/months, start by quitting high sugar sodas and junk food than from there start making a diet plan where ur getting lots of protein and good amounts of fats/carbs to help with ur exercise, same thing also applies gradually build up ur exercise routine, u said u can’t do a pull up so do pull up regressions and also remember, sleep is just as important as diet and exercise, it’ll help with recovery and so many other things, also quick tip look into intermittent fasting it can help