Generate XML-response without any html code.

Hi, I need to generate an XML response on an empty file in the public domain.
How can I check my collection for a specific entry and generate an xml response?

I have a example of the link, it’s seems like https://service.someprv.ru/payment_app.cgi?command=check&txn_id=1234567&account=4957835959&sum=200.00&pay_type=1&trm_id=4151200&data1=123456

And I need get parametrs, by a $_GET method and check my collection for a specific entry

Try searching the forum, you might find something useful…
https://www.wix.com/corvid/forum/community-discussion/get-xml-response