The integration between Jira Cloud and Slack does not allow you to create a new Jira issue directly from Slack.
You can, however, attach a Slack message to an existing Jira issue. Take a look at this Slack documentation article to see what you can do with the existing Jira - Slack integration:
I have multiple projects that use variations of the same base workflow. The variations depend on the requirements of the project or issue type. The variations mostly come in the form of new statuses ...
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