There are 2 ways to use BW with Umbrel node:
- connecting to LNDhub Bluewallet Lightning app in Umbrel. Here you have a guide
- only using electrum server from your node to validate your onchain txs, but for this connection go to connect wallet - electrum and use that onion address in BW. Remember to activate Tor service in BW (if you use latest version) or add BW into Orbot (if you use an old version of BW).
Optional use: using the 24 words seed, you can import the AEZEED Umbrel wallet into BW, just as a backup onchain.