I need customers to send their logo

I need customers to email there logo. Is there a way to either link an email to send logo or a field to insert their logo?

You can add a File Upload field in your form where your users can upload an image. Please check these user guides:

How-to-Create-File-Upload-Forms
How-to-Change-the-Allowed-File-Types-in-the-Upload-Field
Changing-the-File-Upload-Size-Limit

Your users can open the form by providing the direct link to them. Here's a guide: Where-to-Find-My-Form-URL.

Hope that helps. Thank you.