Start with running your oven through it’s pre-set ‘cleaning’ cycle. Open up a window as it will get very hot.
After this, wait a few hours for everything to sufficiently cool down and apply a baking soda/water mixture to coat the entire interior. Once that has dried to a light film, use dish soap to clean it away. A vinegar/water solution to kill the final bacteria and caked on smells will have your oven smelling and looking great. For added safety, unplug the oven if possible.
Home pros suggest not removing any knobs to clean underneath as that is a frequent source of electrical shorting and subsequent repair.