What you need to know about PHP to run an online store on OpenCart?

Question

PHP

I know the basics of programming, php syntax. How difficult will it be to make a simple IM with the integration of payment systems?

Answer 1

Put the open server on the LAN and deploy opencart, then look at how the plugins are installed and poke. Nobody knows your level.
To deploy a store, it is enough to know how to upload files to the hosting, fasten the payment - most payment systems have ready-made plugins, put it and poke it.
Install this assembly opencart-russia.ru