The installation services are usually from 100$USD upwards, if I’m not mistaken.
If you want to do the install yourself, you don’t need more than an SSH client, which is installed by default in Mac and Linux, or with something like PuTTy or Windows Subsystem for Linux (WSL) for Windows.
And you can follow step by step from here discourse/docs/INSTALL-cloud.md at main · discourse/discourse · GitHub