HTML form with sending data to the post

You need to make a form in the form of a table (5 rows. in each line 4 columns.)
There should be a dynamic addition of strings.
When you click on the "send" button, all the data must fly to the post office.

Nuance:
html part will be located on the lpmotor landing designer and there is no way to place php files. Accordingly, the php part will have to be placed on a third-party hosting.