Contact Form 7 is one of the most popular and oldest WordPress contact form plugins around. Install the Contact Form 7 plugin. Create a new form with Contact Form 7. Insert contact forms into your WordPress website.
Contact Form 7 can manage multiple contact forms, plus you can customise the form and the mail content flexibly with simple markup. The form supports Ajax-powered submitting, CAPTCHA, Akismet spam filtering and so on.
More information: https://en-au.wordpress.org/plugins/contact-form-7/