Where can I visualize Ramachandran plot? I am using Rampage webserver to obtain a Ramachandran plot. However, the server does not reveal any plot just values (favored, allowed, outlier regions).

Can you recommend other similar web sites?
Here is a page with several suggested methods. I agree that Rampage looks the best of the options, but it seems that it provides some suggested workflows for drawing it in R so that it is very customizable and you can probably get it to show any features you want if you're willing to customize a little.

Here is a Python tool for drawing Ramachandran plots.

There are additionally several other servers/tools.