How to realize jira field linkage

[xixi li]

Hi, community members.
I've encountered a problem with a jira usage scenario, and I'm looking forward to any assistance I can get from the community.
I would like to be able to set two fields to support linkage when a jira issue is created, for example, A and B fields are linked together. This way, it can be supported whether I am creating it or editing it.
I don't know if there is a configuration for this or if it is done through a script.

[Brant Schroeder]

@xixi li Are you asking to keep two fields in sync?  If yes then you should look at automation to do this.  If you are trying to link issues I would suggest using issue links.