WordPress is so popular. Todays, wordpress is not just a blogging scripts. There are a lot of developers make themes and plugins for wordpress and then make wordpress a magazine, portal, or even an e-commerce platform ie. WooCommerce.
This is great for developers who want to make applications website. If you know basic of wordpress templating then you can make a plugin or themes for your applications. Some applications need form as an input from the users. You can design yourself a form but using another people plugin is a smart choice than you develop it from stratch.
There are a name called rocketgenius who create gravity forms. The creator make a wordpress functionality by providing a good form creator. Form may contain name, email, text, and any other things such as image. Some of them are using complexity like an encryption. This is can be handled using third party plugin like gravity form from rocketgenius.
There are also another plugin you can use, some of them even free to download from the plugins download page. You must be ever heard about elementor, there are free and paid version. Paid version contains a lot of more design and page elements such as a form.
You can use any other plugins that can be use for another purpose like form processing and lead capture. There are a name called thrive. You can thrive visual creator and thrive lead that can show and capture lead by showing a popup, in header, bottom, and siderbar lead generations.