Reducing inflammation is surprisingly easy, which is why most people just don't do it (they want an expensive magic pill instead of just using methods that actually work).
First, remove the largest inflammatory things from your diet: no grains, no refined sugars, no processed meat, no dairy (unless it is truly fermented, such as hard cheeses and true greek yogurt), and no legumes.
Second, walk about 2 miles a day (at least 5000 steps), and frequently (preferably every two days, but not everyone can do it this frequently) do lifting, preferring higher weight over higher reps.
Third, sleep properly. Enforce a proper sleep schedule as if it's the last thing you do, even if you have to wear sleep masks and avoid bright and/or blue artificial light like the plague.
Fourth, after the first one, still make sure you're getting the proper nutrition (focus on your minerals, you never get enough), and you may still have to supplement with a good vitamin. NOW Adam softgels is the least expensive one I know of that isn't garbage, and is a good base to build a supplement program around (if you choose to do that).