Welcome to the OneStream community lsrinivas2k13 . I think your best bet is to jump in and check out the free content in Navigator @ https://onestream.thoughtindustries.com/learn/dashboard. There is a bunch of content in there that doesn't require a subscription from courses to videos.
There is also the OneCommunity Blog which has some good beginner content. Make sure you go back all the way in time to see what is there. I think there is even some beginner .NET stuff there from memory. https://community.onestreamsoftware.com/t5/Community-Blog/bg-p/blog
Lastly I guess I need to mention the documentation if you haven't been there already. https://documentation.onestream.com/
Good luck!