Is this world real ?
You are asking an interesting but largely theoretical question. What do you mean by real? When using the world “real”, if you mean to ask, “Do we really exist”? The answer is that as far as we are concerned we definitely exist, and our world is a real world with real consequences. The torah teaches us that our actions, positive and negative have a real effect on us and the world around us, therefore we are accountable for everything that we do, and this is why G-d has commanded us to live our lives righteously.
On the other hand, in contrast to G-d’s existence, according to the Torah, we and our whole universe exist only because of the will of G-dand the second that we ceweases to have tht will, we will cease to exist. Therefore the existence of G-d is the only real existence, neverthe less, our existence, as far as we are concerned is also real, as has to be taken seriousely.