I like VSO (Visual Studio Online) functionality and its abilities. But I want other users (anonymous) be able to view my repo of certain project.
I'was trying to work with the security stuff in project settings, but can't figure out how to set a public access to my repo.
Is it even possible?
Your best bet is to sync the two, as outlined in this post.
At present, no. VSTS is not currently intended to be a public code repository like GitHub.
Update
As pointed out in the comments, public projects are an upcoming feature. https://blogs.msdn.microsoft.com/devops/2018/04/27/vsts-public-projects-limited-preview/