To connect the wallet in order to send sats you need to go on the coinos settings->settings->Nostr integration and copy the NWC link. That one then you enter to the Nostr app under wallet settings they all have now to paste NWC code.

I made a guide here https://satoshis-plebs.com/nostr/ (step 7) and talked about it on episode 195 on the nostr:nprofile1qqstmtvzy97pdgevvyclcdgus043mp9en9fhmq9s9qyvsqdv69rznzqpzdmhxue69uhk7enxvd5xz6tw9ec82c30qythwumn8ghj7un9d3shjtnswf5k6ctv9ehx2ap0qyvhwumn8ghj7un9d3shjtnndehhyapwwdhkx6tpdshsn4js34