Clean installaion but grub is somehow encrypted as well

I have deserted the broken suse that couldn’t boot. It was a UEFI dual boot system, but only windows can boot fine now.

Since my laptop can be added for another disk. I have inserted this new disk and tried to clean install openSUSE on this newly formatted disk.

The partition scheme is like this 500GB sda:

sda1 300MB FAT mount on /boot/efi
sda2 300MB linux native (not formatted and not mounted) I don’t know what this is for but suse always suggest a partition like this, so I leave it here.
sda3 400 GB encrypted lvm partition as physical volume SUSE

under sda3 there are two logical volume which are:

root 100 GB ext4 mount on /
home 300 GB ext4 mount on /home

After installation, a first password prompt is “trying to decrypt master key on hda0 part3:”. So I give the encryption password.
Then the grub appears with OS choices, I choose opensuse. Now another plymouth password prompt comes to for cr_*****sda3.

How am I supposed to get rid of the first pass prompt prior grub appearance?

Make /boot separate unencypted filesystem, not part of / (root).

After tremendous numbers of attempts this is finally working. Hope the new system doesn’t break too soon.