To add a jotform to your website signup for an account here.
Once you've signed up for an account you can begin making your form by clicking create a form. You can either start from scratch, or use one of their premade templates. Add all fields that you want your website's visitors to fill out.
Once you're satisfied with how your form looks click publish:
Click Embed on the left sidebar and make note of the code:
Select App Integrations
And then select Third-Party Integrations
From here click to add an integration and find Jotform in the list:
You should now see a field where you can enter your code from earlier:
Press save, this will take you back to your list of added integrations. Toggling the switch will enable the ability to add the form to your pages.
Navigate to the page you want to add the form to, and click the add a section button. You will be able to see your form under the category "Section Integrations".
Once you've added it to the page that you want the form to show up on click publish and it should appear on your live site.