We are going to create a Ubuntu instance on Amazon Web Services. After creating an account select the "EC2" product and on the dashboard click on "Launch Instance".
Select Ubuntu Server 18.04, then select your Instance Type. If you want to use the free tier, select "t2.micro" and click "Review and Launch".
On the review page, click on "Edit security groups". Configure SSH (22), HTTP (80) and HTTPS (443).
Create a new key pair, download the .pem file, then launch.
Connect via SSH:
chmod 400 your_file.pem
ssh -i your_file.pem ubuntu@xxx.xxx.xxx.xxx