Create BTC transaction from WAN

I am a newbie here.
I installed Umbrel on Rasberry pi successfully and ran the latest version (5.2) without any issues.
My goal is to send BTC transactions from WAN (from the Internet) to the Bitcoin node in Umbrel.
Any advice/guidance greatly appreciated.

(my idea is to create a full string and use [bitcoin-cli sendrawtransaction “signedhex”] directly to Umbrel)