It seems like I’m just a few hours work ahead of you as I went through similar challenges over the weekend. From the information above, I assume you are using Contact Form 7. It seems to be good but it does take a minute to get orientated.
I think the missing step you need is to use the “Generate Tag” function (see image attached) for each field that you want to have on your form. Once you’ve done this, you get a field reference, something like [text-123], [email-888], etc. You then need to:
1. insert these references in the form so that the plugin knows what input to associate with each variable
2. insert them in the mail that you will be sent, so that the plugin knows how to map them to the message you get
When this is done, your mail’s “From”, for example, will look like this:
…if you’ve used [text-123] for the sender’s name, and [email-888] for their email address.
You can see a telephone reference in the image attached, which has a theme class included. I hope this helps. By the way, if you are using Contact Form 7, you might want to check out the plugin “Contact Form 7 Honeypot”. I’m not sure how good it is but it could help you defend against getting spam through the form without requiring people to struggle with captcha trials.