From ubuntu 16.04 to ubuntu 20.00

What i did

sudo apt update
sudo apt install update-manager
sudo apt dist-upgrade
sudo do-release-upgrade -d

I was asked to reboot when I typed the last command. Installation is completed in about an hour.

Reference article https://qiita.com/hitobb/items/2ee9b1c2c49760976e0f

What I did after installation

https://qiita.com/outou_hakutou/items/ce06cb3c8c355d5fd87c