Hi @subhampradhan,
You'll want to head over to the Contact Instructure | Canvas Customer Service page and either give Instructure a call at the number listed, or fill out the contact form on the right while selecting the "I want to connect with sales" option. The Instructure Community is make up of other users (admins, teachers, students) of Instructure products, like Canvas. While users are able to answer a lot of questions about using Canvas, pricing has a ton of variables and won't be something any of us could even give you an estimate on.
-Chris
