Where can I see HR EHP level?
Driling down through system status and into component version for EA-HR the release is 604, the level is 0034. Does this mean that HR is on EHP4 and pack level 0034?
Yes that is what the system status information means.
You can see more detailed information in Transaction SPAM:
Package Level should be SAPK-60434INEAHR if it is EHP4 SP34 for EA-HR.