Check how much disk space is available on Ubuntu

df -h

udev            474M     0  474M   0% /dev
tmpfs            99M  1.1M   98M   2% /run
/dev/vda1        25G  6.7G   18G  28% /
tmpfs           491M     0  491M   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           491M     0  491M   0% /sys/fs/cgroup
/dev/vda15      105M  5.2M  100M   5% /boot/efi
/dev/loop3       68M   68M     0 100% /snap/lxd/21835
/dev/loop6       56M   56M     0 100% /snap/core18/2253
/dev/loop10      56M   56M     0 100% /snap/core18/2284
/dev/loop7       44M   44M     0 100% /snap/snapd/14978
/dev/loop1       62M   62M     0 100% /snap/core20/1361
/dev/loop5       68M   68M     0 100% /snap/lxd/22526
/dev/loop0       62M   62M     0 100% /snap/core20/1376
tmpfs            99M     0   99M   0% /run/user/1001