Learning English is like climbing on the mountain and you don't know how high it is. Suppose, I climbed to the height of 10 meters and you climbed to the height of 20 meters. When you look down back, then you can see me on the same place, from where you have passed some time later. After that I asked to you that how much time it will take to me reaching there on your place?

Learning English is like climbing a mountain, a mountain whose height you don't know. Suppose, I climb up 10 meters and you climb up 20 meters. You look down and you can see me right where you once stood. I would like to know how long it takes to get from where I am right now to your level, and what it takes to get there. Very nice metaphor. It is ok to use present simple here, as you paint the picture of the situation and you generalise. I think saying where I am right now to ‘your level’ is more closely related to learning the language. You also probably want to ask : what it does it take to reach your level? It’s not a question about the time but what it required, needed, in terms of resources, character etc.