Connect payment system (epay 2.0) to self-written payment module

There is a payment epay 2.0
And there is a self-written payment module on the site, it is implemented as simply as possible. A couple of PHP functions and conditions and thats it.
CMS DLE
Epay 1.0 is now installed, but it is outdated. The thing is that despite the versions, these are completely different payments.
You just need to connect a new one. And this requires knowledge of PHP and JS.
Write immediately terms/ amount/ your telegram for communication.
Thank you!