My English grammar knowledge is very weak, how can I create a good foundation(kind of hoping to get a refresher from the ground up to end) of English grammar (which would also help me in real life) and improve further which is needed for GRE verbals and essay writing. any suggestion would be really helpful.
I know, this is not exactly you are looking for. But, just check, if this is going to help partially. A 16 sessions collection on ‘Dedicated Grammar for GRE’.