First use lsblk -f to see the drives you want to mount UUID.
Then create a directory where you will want to mount your drivei.
Edit /etc/fstab with your text editor and add this line:
UUID=your_uuid_here /mount_directory ext4 defaults 0 0
Replace your_uuid_here with drives UUID and /mount_directory for your directory.< /p>
Use sudo mount -a to test the config. Afterwards run sudo systemctl daemon-reload.
And again sudo mount -a to mount it. Now it should auto mount on boot.
That's all.