I am thinking of buying a laptop with 16gb ram 526gb ssd and i7 but I can't think whether to choose 6 cores or 4core or8core.Will a quad core laptop be good for running Android studio smoothly as it will save me some money
Well "best" would be the fastest system you can afford. You did not actually list the full specs of the laptop or price vs what others you are looking at. Based on what you listed for the specs it will run the programs you need without issues. You asked for what will save you money, therefore "best" is not what you are looking for.