When a ticket is marked as Done or Achieved, how we would like it to also be marked as Resolved.

[Deepika]

can you please let me know the steps to make resolution field editabl

[Aditya Sastry]

On Moving the issue to Done or Achieved, add a transition screen with "Resolution" system field in the screen.

Once you select the resolution field, it gets set in the issue and it is transitioned to the desired status.

[Joe Pitt]

Resolution Field can't be made optional. DO NOT put the field on any screen except the one presented in the transition where it is to be set. Resolution is a special field in JIRA. It has an initial value of ‘Unresolved’, which means the field is NULL in the database. It is ALWAYS required when it appears on the screen. ONLY display it on the screen during a transition to the status where you want it set. Once it is set the issue ID will appear with as strikethrough. If you reopen an issue the transition from closed to reopen needs to have a post function to CLEAR the resolution field to set it back to Unresolved.

The way to allow updates is to create a transition going back to the same status with the resolution field on the transition screen. 

Limiting resolution options

Use the jira.field.resolution.include workflow property

for exampl jira.field.resolution.include =1,2,3  where 1,2,3 are the resolution ids

https://confluence.atlassian.com/adminjiraserver071/workflow-properties-802592825.html