Permission limits for different users of ERPNext

Frappe Framework Permissions
1

I wish to give permissions for specific modules to the relevant departments. How does that happen?

For eg. Accounts department is only able to access accounts module

2

@rjridhi12: you may want to review http://frappe.github.io/erpnext/user/manual/en/setting-up/users-and-permissions/ as a starting point for your research and permission customization.