how much is far enough to go on first date?

Unless you have known the person a long time, or it is someone you really feel a physical bond with or just know they are the one for you, I feel a first date is just something in which you need to test the waters elsewhere as just get to know the person you are with, and see if they are the right one for you.

A kiss is sometimes too much, unless there's chemistry between both people and they both know it.

On a first date, sometimes a kiss is far enough to go on a first dat. Sometimes it is not. It depends on the couple, their ages, maturity, chemistry, etc.