Hello Akshay, 

This is something that depends on individual colleges. Your year gap should not pose a problem but they might ask you to explain what you did during this off period. As long as your answer is satisfactory, it should be fine. Some colleges ask for a gap certificate/letter in case you have such year loss. In this case you will have to submit the letter/certificate in the format mentioned by the college.  Most colleges will not stop you for this. But some colleges do have a policy of not admitting gap students (they are fewer in number). 

As for documents,  that too will require your usual documents such as marksheets,  aadhar card,  attested documents, etc (depending on your college).  

Mention a particular college next time for a more specific answer. 

Hope this helps :)