When a page in Confluence doesn't follow a workflow, we need to make it under workflow process.
Please find below the steps that helps to make a page follow the workflow process
Step 1: Navigate to the Space Tool option.
Step 2: Click on the Comala Workflows option
Step 3: Navigate to Configuration Tab
Step 4: We need to change the parameter in workflow configuration of the space from Published to Latest
From This
To This
Step 5: Then after updating the page, the button to use the workflow is visible