Do one of the following:
Set a filter: Choose a filter (such as Only from VIP) from the menu. A checkmark appears next to the filter.
If you use more than one email account in Mail, you can filter a mailbox by account—for example, you can filter the Inbox for just your iCloud account to show unread messages.
Remove a filter: Choose an active filter from the menu. The checkmark next to the filter is removed.
If you have multiple Mail viewer windows open when you set filters, the filters are applied only in the active window. If you open a new Mail viewer window after setting filters, the filters are applied in that window.
Go to the Mail app to indicate that no filters are applied.
If you have a Mac with M1 or later, Apple Intelligence can prioritize your messages, so you can quickly view your most urgent emails. See Search for emails in Mail on Mac