Need Help to start Quant from level zero

worship google like god if you want to reach good score from ZERO.

Platinumguide dot com is the free resource for quant, you can check that. It is really well explained, as you are starting from zero you may need to search some terms that you are not aware of.

Just keep going through topics first before attempting any questions. otherwise you will be nowhere doing half bit of both ends.

Whatever you do, make sure you study your math before you start studying for the GMAT. There is absolutely no use doing GMAT problems at this point if you're uncomfortable with the underlying concepts.

So, take the next few weeks, and don't even open a GMAT book. Instead, get yourself some basic math books (something like "Algebra for Dummies" ... I've also had students use "Secrets of Mental Math" with good results) and study those until you get better at math. Then, and only then, will you be ready to start doing GMAT problems.

I know it's temping to just start working problems, but trust me: you'll get a whole lot more out of it if you "get" the math and instead focus on speed and methodology. A little time spent up front in this regard might save you lots of time down the road.