Obese guy starting out

So I'm trying to lose weight for a lot of reasons (embarrassment, self esteem, health concerns etc). So i've started following this as I don't have access (or would feel particularly comfortable rn) going to a gym and later in the day once i've recovered walking up the entire staircase in my block of flats (14 flights) and back down to my floor (4th floor). My diet now consists of 2 pieces of fruit in the morning (some combination of pear, banana and orange) and a meat based dish in the evening. I'm not the best cook so for now this consists of some chicken thighs or some lamb or something basic like that alongside lots of water (and ribena/squash as a substitute for fizzy drinks) to keep me going.