Its a great sentence I ever seen..
"I have no issues if for experience only I have to work for less or no money for some time..but can I plan a future or start my job career on this?"
But don't worry its not happening to you...
I suggest don't go for the certificate first...
At first read about SAP, learn SAP from anywhere without any certification course...
To get start, read about SAP ERP, like
What is ERP?
What is an ERP package?
What is SAP??
What is a business.
What is called business process...
First you have to know about business process...
Then as per your interest choose a module of SAP. Then involve in this particular module.