the TO address is the email address that the email will be sent to.
there is no one correct answer for what you should use here, it depends on what you are using the form for.
Do you want the email to be set to you? Then use your email address in the to field.
Do you want the email to be sent to person filling out the form? Then bind the to address to the email address form element.
same with the from address. Where do you want the email to come form? The person filling out the form? or you?