I would leave both on " Auto".
Auto means that BIOS will decide when to use that feature. If you "Enable" PBO then it will be on all the time.
If are having issues you can disable PBO or Core Boost or both for troubleshooting purpose in the future.
You can, if you want to, enable PBO and see if you have any problems or not. PBO is AMD feature for safely overclocking your Ryzen processor automatically.