Low oil pressure?

Where is the noise coming from the top end like valve train or the bottom end like a piston. Can you please shoot a quick video with your phone so I can hear the noise? that way I can tell for sure what's going on. You can upload it here with your response. Also, if the engine has an internal problem, it can have low engine oil pressure or if the oil pump pick up is clogged with sludge.

Please check out this guide:

https://www.2carpros.com/articles/high-or-low-engine-oil-pressure

Please go over this guide and get back to us.