Is there a way we can access customer info like, email and name on a product detail page and access as a variable (like a handlebar variable)?
You can use the Profile.Model and then get the instance of the profile model like ProfileModel.getInstance(). There you can get the Customers data.
The other way of doing that via backend is using the Commerce API customer. It is inside the Models.Init module.
These are the methods that is available under Customer API