My guess is that you are on JIRA Cloud. The add-on is not available for Cloud.
If my guess is wrong and you're on Server, then yes, you can install it from the marketplace from inside the "find new add-ons" under admin. Or, if your server can't reach the internet, download it to your machine and use "upload add-on" to upload the jar.
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs