My kia optima leaks engine oil around the filter

This is usually caused by not putting a film of burned engine oil on the rubber seal when replacing the filter. It could also be caused by not removing the old seal when removing the filter and then putting a new seal on the filter and screwing it on, thus having two seals on the filter which would cause it to leak. What I would suggest is to remove the filter using a filter strap and make sure there is only one seal on it and cover it in a film of oil and screw it back on hand tight. Run the engine and make sure there is no leaks. Top up the engine oil if necessary.

Remove the filter and be sure the is a rubber gasket attached, if so rub a bit of oil on it before replacing, being certain that interior threads are clean and not stripped ( if so replace filter) only turning hand tight, no not overly tighten.

Make sure that the leak is not running down from higher up the engine (clean it with some degreaser and run engine, look for any signs of oil) If you are sure that it is lower down the first thing to check is to see that the oil filter has been fitted correctly (not left an old sealing ring on it) so I would unscrew it and check also check for damage on the seal you are re-fitting. clean off again and check for any oil leak by now you should be able to see where it is coming from which will probably be the housing and will need a new gasket fitting, If you are attempting this yourself make sure all parts are clean and tightened to the correct torque.