You can show Checklist Progress (or another checklist custom field such as Checklist Progress % or Checklist Completed) on cards in Jira boards:
Note that this is currently only possible in Jira Company-managed (Classic) projects. Team-managed (Next-gen) projects do not allow you to customize board cards.
To add the field to a card:
Navigate to the project board.
Click on the … menu and select Board settings.
Select Card layout.
You can include up to three additional fields on cards in Jira boards. Use the dropdown to select the Checklist Progress field (or whichever field you want to add).
Click Back to board. Cards will now show Checklist Progress.