Microsoft Dynamics NAV Training and Certification Details
If you have a Subscription for Microsoft Dynamics Learning Portal,
then you can go here (it’s not for free):
you can also use NAV 2015 videos.
For that follow https://msdn.microsoft.com/dynamics/nav/dn783472
check also the msdn tutorials
additional materials/tutorials you’ll find on youtube and in the blog section of that nav forum.
Microsoft Dynamics NAV certifications Path: