How to create content fields and use in new page layout.?

You should follow the mentioned steps below to create a custom page layout with the required field controls like content field and image field.

• First of all Specify, the field controls that you need to show within your custom page layout. like content field and image field.
• Create a site content type.
  • Go to Site Settings > Web Designer Galleries > Site Content Types.

• Click Create.

• Under Parent Content Type select Publishing Content Types then Page.
• Now Click on Add from new site column to create content fields and image fields.
• Set the name of your columns and Select Full HTML to content field and Image with formatting for Image.
• Now go to create a Page layout.
  • Site Settings > Design Manager > Click on Create a Page Layout > set the name of your page layout > select your master page > select your content type that you have just created.
• After the page layout created > Select your custom page layout > and From the above ribbon > select Publish.
• Now go back to your page that you need to use the custom page layout within it > edit it > select your custom page layout > you should now find the content fields and image fields and other fields that have been created within your custom page layout.