From setup page navigate to Objects & Fields -> Object Manager.
On clicking ‘Object Manager’ you will be redirected to the Object Manager screen.
By clicking on the ‘Contact’ module, you will be navigated to the Contact details page.
Click on ‘Page Layouts’ to manage the contact page layout.
On clicking ‘Page Layout’, you will be presented with the Page Layouts page. Click on ‘Contact Layout’ to edit the layout.
By clicking on the ‘Contact Layout’ link, you will be redirected to the Edit view of the Contact Layout.