DigitalOcean is a good place to start. I like their droplet system, it’s easy to destroy and recreate if you messed things up.
A droplet at 10$/month will be enough. I use OVH SSD but I’m french, I don’t know the value of their services somewhere else. You have some options here :
I never used a terminal before Discourse, it’s challenging at first but if you follow the install guide seriously, everything will be alright. I run a dozen of Discourse forum, it takes me 30 minutes per week to manage, so it’s pretty easy