My first place to start is the farmers market at Noordermarkt, which is great for plastic free groceries like fruit, vegetables, nuts, bread and grains. Bring your own bags and jars and most stalls will happily oblige you. For your other purchases try the following:
Natural Heroes: for all your ingredients to make your own beauty products, products are in glass bottles and they only use paper / cardboard that can be recycled for their deliveries.
Leven Zonder Afval
Plastic Free Amsterdam