Form PHP

Hello guys,

i’m here to ask if anyone would be so nice to help me understanding something i can’t get alone.

I would need to add a HTML form i made which redirect to a PHP script the data doing something like sending email, and other things. I wrote everithing in HTML and PHP and is running on my simple HTML website, now i would like to move the website to worldpress but i got lot of problems doing this because of this form.

what should i set as action?
where the php page has to be insered?

would be nice if i could send my files to someone so to understand what i’m saying.

Thank you for reading, is much appreciated any help and sorry for my english.
Thanks,

Teo.