Help with button

So in my form I have a check box or radio button (doesn't matter which) that when I click if activates the script

sendmail

[

from:zoho.loginuserid

to:input.Agency_Email

subject:"Message from Nigel L Cross (Kent)"

message:input.Email_Message

content type:HTML

]

What I want is to have a button within the form that does this instead of using a check box or radio button.

Is this possible please

Thanks.

Nigel