How to use new internal SSD?

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I have a desktop computer running Fedora 28 with a 2TB HDD. I have recently inserted an internal Samsung 500GB SSD. I wish to use both HDD and SSD. The SSD appears to be recognised by the system (see output of "fdisk" below). However the SSD does not show up as free space in the file system (see output of "df" below). How should I proceed?

a) Re-install Fedora 28 on HDD and SSD

b) Do some magic which exposes the SSD to the file system?

df -h

Filesystem               Size  Used Avail Use% Mounted on
devtmpfs                 3.9G     0  3.9G   0% /dev
tmpfs                    3.9G   47M  3.9G   2% /dev/shm
tmpfs                    3.9G  2.0M  3.9G   1% /run
tmpfs                    3.9G     0  3.9G   0% /sys/fs/cgroup
/dev/mapper/fedora-root   50G   17G   31G  35% /
tmpfs                    3.9G  152K  3.9G   1% /tmp
/dev/sda2                477M  174M  275M  39% /boot
/dev/mapper/fedora-home  1.8T   93G  1.6T   6% /home
/dev/sda1                200M  8.9M  191M   5% /boot/efi

sudo fdisk -l

Disk /dev/sda: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: A5B5864F-EBBC-4C60-91FA-DFA7616E7CC5

Device   Start        End    Sectors  Size Type
/dev/sda1     2048     411647     409600  200M EFI System
/dev/sda2   411648    1435647    1024000  500M Linux filesystem
/dev/sda3  1435648 3907028991 3905593344  1.8T Linux LVM


Disk /dev/sdb: 465.8 GiB, 500107862016 bytes, 976773168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes