I have installed Ubuntu Budgie 20.04. In my laptop, there is ssd a for operating system on which I have installed Ubuntu and another 1TB HDD drive for data. The drive is shown in the Disks app. I have searched for solution in which I have to make changes in Edit Mount options to disable it. But in my case the option is greyed out.
I have tried another way by using command
sudo ldmtool create all. Which allow me to access the data drive. but it does not mount automatically. There was another command which was supposed to mountsudo mount /dev/mapper/ldm_vol_SPONS_SERVER-Dg0_Volume1 /destination path. But it did not work.
The hard drives (or partitions) that you setup in the gui interface of the disk manager automatically get added to /etc/fstab to be mounted automatically at boot. You can also click the settings icon next to the minus icon and that will give you a menu where you can click an option if you want that partition to be mounted at boot. Also, if you are talking about another partition and you can't mount it through the gui you can see this post on how to manually mount it. Once you have you can go back and make it mount at boot.