part, we want use your app but for CRM part we need to use infusionsoft / Keap :
Please find below example of Form code from infusionsoft / Keap :

<form accept-charset="UTF-8" action="https://xxxxx.infusionsoft.com/app/form/process/xxxxxxxxxxxxxxxxxxxxxxxxx" class="infusion-form" id="inf_form_9f0c9152c637d239c813a90e532f6a63" method="POST">
<input name="inf_form_xid" type="hidden" value="xxxxxxxxxxxxxxxxxxxxxxxxx" />
<input name="inf_form_name" type="hidden" value="Web Form submitted" />
<input name="infusionsoft_version" type="hidden" value="1.70.0.419298" />
<div class="infusion-field">
<label for="inf_field_FirstName">First Name *</label>
<input id="inf_field_FirstName" name="inf_field_FirstName" placeholder="First Name *" type="text" />
</div>
<div class="infusion-field">
<label for="inf_field_Email">Email *</label>
<input id="inf_field_Email" name="inf_field_Email" placeholder="Email *" type="text" />
</div>
<div>
<div>&nbsp;</div>
</div>
<div class="infusion-submit">
<button class="infusion-recaptcha" id="recaptcha_xxxxxxxxxxxxxxxxxxxxxxxxx" type="submit">Submit</button>
</div>
</form>
<script type="text/javascript" src="https://xxxxx.infusionsoft.app/app/webTracking/getTrackingCode"></script>
<script type="text/javascript" src="https://xxxx.infusionsoft.com/resources/external/recaptcha/production/recaptcha.js?b=1.70.0.419298-hf-202112131919"></script>
<script src="https://www.google.com/recaptcha/api.js?onload=onloadInfusionRecaptchaCallback&render=explicit" async="async" defer="defer"></script>
<script type="text/javascript" src="https://xxxx.infusionsoft.com/app/timezone/timezoneInputJs?xid=xxxxxxxxxxxxxxxxxxxxxxxxx"></script>
<script type="text/javascript" src="https://xxx.infusionsoft.com/js/jquery/jquery-3.3.1.js"></script>
<script type="text/javascript" src="https://xxxx.infusionsoft.app/app/webform/overwriteRefererJs"></script>