Форма заказа курсов с возможностью прикрепить файл

The course order form allows you to receive a message from the client.
Capabilities:
*Error checking;
*Saving form data in case of errors;
*Reset form data after submitting;
*Ability to attach a file with gzip-compression or without compression from the file MIME types allowed for download.
All features are implemented in the programming language PHP.