Since you have 18000 rank in KEAM, some colleges that you can get with your category rank (backward Hindu) in Computer Science and Engineering  and Information Technology are :

• GEC Idukki (CSE & IT, Govt)
  
• GEC Mananthavady (CSE, Govt)
  
• GEC Sreekrishnapuram (IT, Govt)
  
• College of Engineering, Chengannur, Alappuzha (CSE, Govt controlled)
  
• College of Engineering, Kannur (CSE & IT, Govt controlled )
  

The Government Engineering colleges are the best option in terms of Placements, Faculty and Infrastructure. But you should learn to adjust to hostel life.