Hi MarilynVogel,
Thank you for reaching out to Microsoft Community.
Is this the typecover that you mean was referenced on the website: Surface Pro X Signature Keyboard?
For the pen, is it the **Surface Slim Pen**that you have? or other model? You may check this page to Identify your Surface Pen. Since you are asking how to charge the pen, I assume that it is the Surface Slim Pen that you have because this is the only Surface Pen model that is rechargeable.
If the keyboard you mean is the Surface Pro X Signature Keyboard, it is not compatible with the Surface Pro 7. It is only compatible with the Surface Pro X in which it has the built-in charging cradle for the Surface Slim Pen. The Surface Pro 7 uses this kind of typecover: Surface Pro Signature Typecover.
The Surface Slim Pen though is compatible with the Surface Pro 7 but since the Surafce Pro 7 typecover does not have the charging cradle, it should come together with its USB-C charging base. You may refer to this page for more details to Use Surface Slim Pen.
If in case the pen that you have is other that the Surface Slim Pen like the Surface Pen with no clip, they are not rechargeable pen. See this page for details on How to change Surface Pen batteries.
If this answer your question, we highly encourage you to inform our Community by clicking on Yes or marking my post as an answer. This will help other members who may have the same issue as you. Otherwise, don't hesitate to update us so we can further assist you.
Kind Regards,
Marrion Y.