How many members does each Dutch province get in the First Chamber of the States General of the Netherlands?
The States-Provincial or the Senate?
Representation in the States-Provincial can be found at Provincial council (Netherlands) - Wikipedia
The Senate just is generally elected by the States-Provincial, isn’t it?
There are no provincial delegations. The Senate is elected nationwide by proportional representation, just with only the provincial legislators voting. (Their votes are weighted based on the size of the legislature and the population of the province.)