How to increase Gitea storage space with multi storage devices

Here are my block devices below, and I installed my private Gitea server on Ubuntu 16.04.5 LTS which is installed in a VM, and it is on sda.

lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 500G 0 disk
├─sda1 8:1 0 484G 0 part /
├─sda2 8:2 0 1K 0 part
└─sda5 8:5 0 16G 0 part [SWAP]
sdb 8:16 0 500G 0 disk
sr0 11:0 1 1024M 0 rom

Now I would like to increase the whole Gitea storage space. Is it possible to increase the
whole Gitea storage space by adding the storage device sdb except for increasing sda directly?