Thanks for all the comments and I've re-edited the question:
All nature settings(radius of planet, etc) are similar to the real world earth except the continent layout.
I used Mogensen Planet Generator for the map and recolored it. I am aware that this generator does not consider tectonics, mountain chains, rivers, and climate. So I am mostly concerned about the following elements:
1) Mountains: This seems the priority because it determines the landscape. So far it is determined by fractal generator and it doesn't look very realistic to me.(Just random elevations and there isn't a tectonic pattern) Given such a layout, what is the approach to determine the moutains and valleys? 2) Deserts: Seems many comments have pointed out this problem. Is there a specific region you believe that is impossible to have deserts, or must have deserts?
And if you noticed any other errors in my map, please let me know, thanks!