Hello Mahesh,
Its good you have some plans to learn SAP ABAP and certification but we have very less amount of opening for fresher now a days, Go and learn ABAP then you can try in some middle range company there you can join as fresher, get some experience and then try for big shots.
One More thing : Don't take certification as a job offer letter, certification will help you to find a job but its not your offer letter.
Here..you can learn ABAP online too..