Ubuntu Server 20.04 disk space issue

Hi,
I have a virtual machine running Ubuntu 20.04. I set aside 100G of storage and i follow the prompts to image Ubuntu. I accept all defaults.
I noticed that im running low on disk space but when i check df -h i see that my LVM is using 50G.
Really confused. How do i make the entire disk usable instead of 50G of it.

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
loop1 7:1 0 62M 1 loop /snap/core20/1581
loop2 7:2 0 67.8M 1 loop /snap/lxd/22753
loop3 7:3 0 47M 1 loop /snap/snapd/16292
loop4 7:4 0 67.2M 1 loop /snap/lxd/21835
loop5 7:5 0 47M 1 loop /snap/snapd/16010
loop6 7:6 0 62M 1 loop /snap/core20/1587
sda 8:0 0 100G 0 disk
├─sda1 8:1 0 1M 0 part
├─sda2 8:2 0 1.5G 0 part /boot
└─sda3 8:3 0 98.5G 0 part
└─ubuntu–vg-ubuntu–lv 253:0 0 49.3G 0 lvm /
sr0 11:0 1 1.2G 0 rom

pvdisplay
— Physical volume —
PV Name /dev/sda3
VG Name ubuntu-vg
PV Size <98.50 GiB / not usable 0
Allocatable yes
PE Size 4.00 MiB
Total PE 25215
Free PE 12608
Allocated PE 12607
PV UUID czwrbi-1F32-YhfO-Atyj-WL7c-Ldjd-NzvKDz

Disk /dev/sda: 100 GiB, 107374182400 bytes, 209715200 sectors
Disk model: Virtual disk
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: DED4235F-28BB-419E-B977-C6B8F2F6344D

Device Start End Sectors Size Type
/dev/sda1 2048 4095 2048 1M BIOS boot
/dev/sda2 4096 3149823 3145728 1.5G Linux filesystem
/dev/sda3 3149824 209713151 206563328 98.5G Linux filesystem

Jay has a tutorial on LVM

https://www.learnlinux.tv/linux-logical-volume-manager-lvm-deep-dive-tutorial/

Thanks Tom, figured it out.
lvextend -l +100%FREE /dev/mapper/ubuntu–vg-ubuntu–lv
resize2fs /dev/mapper/ubuntu–vg-ubuntu–lv

I do need to learn more about LVMs so I appreciate the link provided. Checking it out now.