To configure contact form you should change file php/contact.php.
HTML Example:
<form action="php/contact.php" class="nk-form nk-form-ajax">
<input type="email" class="form-control required" name="email" placeholder="Email *">
<div class="nk-gap"></div>
<input type="text" class="form-control required" name="name" placeholder="Name *">
<div class="nk-gap"></div>
<textarea class="form-control required" name="message" rows="5" placeholder="Message *"></textarea>
<div class="nk-gap"></div>
<div class="nk-form-response-success"></div>
<div class="nk-form-response-error"></div>
<button class="nk-btn nk-btn-effect-2-right nk-btn-color-dark-1">
<span>Send</span>
<span class="icon"><i class="ion-paper-airplane"></i></span>
</button>
</form>