First of all for beginner, Discourse is totally free forum software which has large core files. You can not install on any shared hosting, to install discourse software you must need 1 GB Ram which is available only in VPN or dedicated hosting plans not in shared hosting. Check it out the below discourse installation requirement before going to purchase any hosting or installation process.
- Dual Core CPU (Recommended)
- 1 GB Ram minimum with Swap
- 64 GB Linux Compatible Docker
First you need to ask to your hosting company via phone support or live chat, that they have the above hardware requirements in their VPN hosting, if Yes then go ahead with it.
You can not install discourse in any shared hosting plan even business shared hosting plan is not sufficient for Discourse.
Personally, Our this forum is installed on Digital Ocean and at least $10/month is suitable for discourse because it comes with 1 GB Ram.