How do I adjust the autoresponder to have the client email as the sender?

2. How do I adjust the autoresponder email so I can show my client email - not no-reply@jotform.com?

We support this, but you'll have to get MailChimp and Mandrill App which will cost you more since Mandrill is not free, and you also need to be paid with MailChimp to use Mandrill.

https://www.jotform.com/help/240-Set-The-Sender-Email-Address-With-Mandrill-Account

I would also to clarify if you mean the autoresponder, not notification email which is sent to you once someone submits the form. The autoresponder is sent to the submitter. 

In the notification email, you can select the Email field as the Reply-To Email which will be the client's email address:

Hi,
Thank you for your answer.
I am talking about a confirmation email to the user, submitter of the form.
It works, bu I need yo change the no-reply email.
Petur
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You can add custom sender email https://www.jotform.com/help/238-How-to-Add-a-Custom-Sender-Address-to-an-Email-Alert.

If the verification method will fail to work, I would suggest configuring SMTP method to send an email from your server, authenticated via Jotform.

https://www.jotform.com/help/244-How-to-Setup-SMTP-for-a-Form