Yes you can. Centre is there in Guwahati. Sorry for late reply,hope you have already applied. 

Hello Venus,

You cannot appear IIITH PGEE exam from Assam as there is no exam center there. 

The mode of IIITH PGEE EXAM is online mode. You can fill and submit the application form by March 21 St 2018. The exam will be held on April 21 st 2018. 

You can the below link address for more information pertaining to the exam

https://engineering.careers360.com/articles/iiith-pgee

Hope this helps!!