first of all iam asp.net web developer around 10 yrs exp, recently shifted to meteor, done coding and now trying to host app, i have dedicated server centos
1)now how do i keep my meteor app running, now i have to do ssh and go into that folder and type meteor, if i close that ssh, app goes down
You have installed your development code into production. When you deploy a Meteor app (to production) there is no meteor to run - you have a pure nodejs app at that point. Check meteor-up for an easy way to deploy your app to your own server (currently not CentOS).
For CentOS, you could look at this blog, which may help.