PHP Payment Integration & Security Updates

Title
PHP Updates + Payment Integration + Security Tasks

Description
I need a PHP developer to handle a few updates on my existing website.
The site is already running; this work mainly involves small fixes, security updates, and basic configuration changes.

Note:
The payment gateway UI and frontend are already fully implemented. The task is backend integration only (deposit, automatic callback).

Tasks include:
• Integrate 1 payment gateway (deposit only, automatic callback – backend integration only)
• Remove old developer access (cPanel, FTP, DB, test logins)
• Change admin URL & login credentials
• Fix a minor mobile scrolling issue
• Enable free cPanel backups
• Change 1 URL and rename 2–3 buttons
• Optional: install SSL / force HTTPS
• Optional: remove ~15 test users

Requirements:
• PHP experience
• Payment gateway integration
• cPanel knowledge

Budget:
Open to fair offers