Message Custom Field (for edit) to show the "Key" field

[Scott Robertson]

Hi, I am using Jira Software Cloud Version. Is it possible to pull in variables in to customer fields "Message Custom Field (for edit)" or any other fields like this? We are looking to use the "Key" variable to link to a folder we will manually create on our network and us this variable to link to a folder path for example:

Information relating to a Request should be saved on the network here:  \\c:\CS\Requests\"Key".

From searching I cannot see an easy way of doing this however I have found it a difficult thing to work when searching as I am tending to get different returns than I am expecting.

Any help with this would be much appriciated