Depends on the input your PC needs. If it’s a common 19V power supply then you need a 19V PoE splitter like this + an adapter for whatever connector yours has: https://www.ebay.com/itm/194028107173
You’ll also need a switch that can supply 802.3bt PoE.
The usefulness of running a mini PC off of PoE seems pretty small, but there are some cases where it might make sense.
Which one specifically?
Depends on the input your PC needs. If it’s a common 19V power supply then you need a 19V PoE splitter like this + an adapter for whatever connector yours has: https://www.ebay.com/itm/194028107173
You’ll also need a switch that can supply 802.3bt PoE.
The usefulness of running a mini PC off of PoE seems pretty small, but there are some cases where it might make sense.