Umbrel is just a Docker application program running on a what is called a headless or non gui version of Debian 12. If your Umbrel is on a PC you could install a desktop on it. Or a kiosk instance so the web gui is there on the local video port. But regardless you still have to edit files because Linux is an non configued system for that you configure since there is many methods to do network storage.
In your case, you set up the different Drobo shares if you want to use. Then you figure out where you want them mounted in your home folder (that has to be empty or create new ones). Then we create a credential file since that one is password protected system and add its mount entry into a file called fstab.
You could use a file browser app if there is one for temporary uses, but for something permanent on the network, you just permanently mount the share