How do I add attachments to tasks and subtasks?

In order to add an attachment to a task or a subtask, please firstly tap on the task’s or subtask’s title in the list or create a new task or subtask. On the 'New/ Edit' screen, please select the ‘Attachments’ option and then tap on the ‘Plus’ button on iOS and iPadOS, but on macOS, please click on the ‘New Attachment’ option in the ‘Attachments’ section.