Integration of payment services on the PHP JS website programmer and not only

It is necessary to integrate two payment systems with the possibility of choice into the site.
The first payment system Tinkoff online cashier
The second payment system www.unlimint.com

Next, you need to add a conversion from dollar to ruble at the rate of the bank when adding the service to the cart.
Likewise:
Uploading documents to the users personal account with a form for filling in personal data
Referral Management
Upload statistics to Excel
Promo code before payment
Page for referral, to check statistics
Ability to use a promo code by link
Conversion statistics
Set up automatic sending of messages through Mailersend.com templates

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CMS ModX

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