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By now, you should have been able to do all sports except heavy weight training and collision sports. The strengthening exercises for your back should have started as early as three months post-surgery, as the tissues would have healed by then. It is not too late to start now. Start with mobility exercises followed by strengthening exercises.
Running on a soft surface like lawn, etc., is fine for now. You can start jumping after your back has regained adequate strength as muscles act as shock absorbers.
Weight training free weights for the upper body is fine, and machine weights are acceptable as long as your back is supported fine. Free weights for your back and butts will depend on your progress. And again, be sensible that your back is never going to be normal, so trying to lift weights that you lifted prior to injury is not impossible but something with only limited returns.
I hope this was helpful.