Hi Lucas - Welcome to the Atlassian Community!
Jira Service Desk isn't really a separate thing per se. But it's a type of project that then has features associated it that type of project.
So, create a new Project and select Service Desk as a Template type when you are creating the project. See if this previous post helps you a little:
From the Halp Team Howdy! 👋 We’re Halp, a conversational ticketing help desk for all of your internal requests in Slack (and soon to be MS Teams!). We’re excited to be a par...
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