We are using Contact Form 7 plugin for this theme, It’s one of the best contact form plugins for WordPress.
You can use default form that comes after installing this plugin or you can use or customize form like the demo.
Go to the Contact > Add New. Here you will see a default form code like the screenshot below.
Replace the form code by the code below, it will make the form like your demo.
Save the form, and go to the contact page and edit the contact page. Here in the Elementor Widget section, you will see the Contact Form element. Edit the element in the form select drop-down, select the form that you created a few minutes before.
The final output of the contact form looks like the demo. Here is the screen-shot.