You cannot permanently delete Amazon purchase history from your account
You can archive orders to hide them from your default order history view
Sign in to your Amazon account
Go to Your Orders
Find the order you want to hide
Select Archive order
Confirm the action
To view archived orders, go to Account and Lists
Select Archived Orders
Remove items from browsing history if needed
Go to Browsing History
Select Remove from view for individual items
Clear your browser history if you want to remove local traces on your device
Delete Amazon app history or cache from your device settings if needed