You asked
Can I use adapted lenses on the olympus om d e m5 mark ii?
I don't cover lens adapters on this site, so I can't tell you whether a specific adapted lens will work well on the OM-D E-M5 Mark II. The camera's page lists native Micro Four Thirds lenses, and those are the ones I've vetted for it.
If you do adapt a lens, remember the 2x crop. A 50mm lens frames like 100mm on this body, so the focal length converter and the sensor sizes guide will help you work out the real reach. For a no-fuss kit, start with the native options on the Micro Four Thirds mount page.
Written by Claude from this site's pages.