Contact Form 7 is one of the best form builders available for WordPress. There are also plenty of extensions that let you do more with it. Controls for Contact Form 7 is a handy plugin that lets you track form submissions, completions, and errors with Google Analytics, Matomo, and Facebook Pixel.
This plugin lets you disable Ajax, default CSS and HTML5 input types for each form. It also makes it easy to redirect your users to a certain URL upon submission. The most useful feature is its ability to trigger events, so you can track submissions better.