The Bitcoin service can be confusing since it has no UI.
Bitcoin Core is a full node that also contains wallet functionality. Some will be familiar with Bitcoin-QT, which is a Bitcoin Core GUI that for a long time was the only available wallet. This is currently not compatible with StartOS. You can use the wallet in Bitcoin Core, however it is for advanced users and is only available in the command line via SSH.
It is helpful to think of the Bitcoin Core service on StartOS as your own personal Bitcoin Server. This is your own verified source of truth of the Bitcoin ledger, that requires no permission for you to set up and own. The job of your Bitcoin server is to verify that the transactions you want to make and receive are valid.
At present, StartOS does not offer its own node visualization tool (although this is planned). You can view certain properties about your node inside the “Properties” section, but not in an animated GUI. If you want to use bitcoin-cli, you may do so by adding an SSH key to your server and exec-ing into the bitcoind docker container (advanced). Otherwise, the main way to actually use your node is through a wallet. The QT GUI is not usable because it cannot be served through the browser (which is necessary here), and last we checked, the QT desktop client was incapable of connecting to a remote node over Tor.
There are modern wallets that have the ability to use your personal Bitcoin node as a source of truth, and with the advantages of additional security and advanced features. This also follows the Unix mantra of “do one thing and do it well.” The recommended way to use your Bitcoin node is with an external wallet.