Can i upload a logo to form?

You should be able to add an image to your form by adding the "Image" field under the "Form Tools" section.

You can also use the Form Designer Tool, you can click the "Form Cover" section there to add an image on your form. Here's guide on how to use that tool: http://www.jotform.com/help/300-Form-Designer-Tutorial-Let-s-create-fantastic-forms- 

Do let us know if you need more information on this.