[HELP] Contact form don't send me mail

What contact form plugin are you using?

Im not using a plugin im just using code
<form action="mailto:[email protected]" method="post" enctype="text/plain"> This is what I added
Uhm should I search a plugin right?

Yes – you really do need a contact form plugin. I recommend trying https://www.ads-software.com/extend/plugins/contact-form-7/

I see thanks, and If for example I want to add an Opinion form? can I use this one or must search other plugin?

You can use the same plugin to create multiple forms.