regarding your knee and sprinting, you can do your sprints on the bike or elliptical...basically following an hiit routine. you can also do sprints while swimming if that is a possibility for you. hill sprints on soft ground might be a way to try some running sprints that will put less stress on your knees.
as for lifting, the five exercises mark recommends are basically the major lifts with a barbel: squats, bench, overhead press, deadlift. i would stick with planks or bodyweight ab work for now, and--personally--i think that pull-ups and chin-ups are better than anything you can do with weights, like lat pulldowns or curls.
welcome to the journey. you're going to feel amazing.