Head gasket sealer can get out out of a jam ... while also preventing leakage of coolant and oil into the cylinders. If there’s a leak or issue, it should be dealt with soon so that no further ...
An oil leak from the main seal, also known as the rear crankshaft seal, will usually drip from where the transmission connects to the engine, though it may show up elsewhere, such as on the oil pan.
The head gasket is there to maintain compression while also preventing leakage of coolant and oil ... sealer, be sure to check back on your car after a few days to ensure there are no more leaks.