You can use that for all sorts of exercises, from rowing to bench press to extensions to curls to squats and cover some but not all of the basic exercises. However, the weight used might start to limit you, for example on squats and benches, without a rack. It would be useful to get some kind of used bench with a rack. Also use the bar with your feet under it for situps and do some other ab exercises that don't require weights. Try to find somewhere that you can do pullups. I would hit each muscle twice weekly on a 4-day split.
The diet as mentioned is huge, then throw in some outdoor runs. 3 times a week if you're not worried about weight that's been gained, 5-6 times a week to lose. You can start part jogging part walking, build up the speed over time to a one mile run.