How do I tell if my business uses Jira Cloud or Jira Server?

Short answer is to look at the URL address bar of your internet browser.  If the URL name is “yourcompany.atlassian.net”, then Atlassian is hosting Jira. This means you are using Jira Cloud.  Your business can purchase a subscription and use the EasyKAD™ software.

This article from the Atlassian Community might be helpful if you need more details:
https://community.atlassian.com/t5/Jira-articles/Which-type-of-Jira-do-I-have/ba-p/1342306