Welcome @karthicklinganathan to the Meteor Forums 
The changes between these versions are huge (which you can see when reading the history file) and you might have to invest a bit more time to figure out where to start.
You will also have to tackle upgrading deprecated or abandoned packages or replace them with their NPM counterpart (some packages were just wrappers for npm packages back then).
The big question is how large your project is, where the heavy lifting is done (server vs. client) and if you want to keep in the frontend you have chosen back then (I assume Blaze for 1.1?) or if you may start with a new project and try to integrate the core business logic with fresh new components.
If you provide us with good details we might be able to guide you through 