This guide describes how to link to content from within Confluence.
Step-by-step guide
Create an anchor and create link to an anchor: https://confluence.atlassian.com/doc/anchors-139442.html
Insert links: https://confluence.atlassian.com/confcloud/insert-links-and-anchors-724764900.html
How to add a link to a Jira issue
By using the Insert Issue/Filter under the + function , you can search for the original request.
Once you have established the link, the issue will show a WIKI link to the Confluence page.
Example:
In the issue itself it will be shown as follows under the Issue links, mentioned in:
Display options:
Single issue: 
Total issue count: 
(when only 1 issue selected display option is greyed out)
Table: 
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Overview
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