External Access?

I just set up a new ds223. I went to the external Access settings-->router config-->setup router and found my router and it seemed to push some setting to my router? I looked in the port forwarding on my router. and I don't see any rules applied there... so what did that do?

I can still access my NAS through quickconnect while off site,which is all I want. I don't want an actual port forwarded to the NAS due to security concerns. Just confused if I messed something up already.

Should I change the default port on my NAS as well?