How can I change directory on bash on Ubuntu on windows?

Question

I cannot change directory like this

I have a problem like this:

Answer 1

It's because you're passing two arguments to cd. The cd Ashikur Rahman (notice the space) for most commands is something like two separate commands: cd Ashikur; cd Rahman (in cd case 2-nd argument would be just ignored though).

You'd have to enclose the part with space into quotes, like:

$ cd "Ashikur Rahman"