The manufacturers plate should be somewhere obvious at the front of the vehicle (on my Laika it's on the side of the passenger seat box).
These are maximum permissible weights.
The actual (real) weight will be specific to your own van depending on what options you've added (or taken away) and if you want to to know the weight empty or full (of water, fuel, provisions, clothes, etc.) The only way to know this is to load the van as you want it and take it to a weighbridge.
usually the plate will show 4 weights
the vehicle gross weight
the vehicle axle weights
and the gross train weight this is max with a trailer included and is always the highest figure
i assume there will be 5 weights if its tag axle
none of these will tell you what the van actually weighs
unladen weight may be on the v5
or as said its a weigh bridge job
5600kg is the Max Train Weight on our Laika - most info I can see on line Gross Vehicle Weight is 3850kg. If you give us all the figures on the plate we will be able to tell what the Max Permissable Weight is.
Whatever the Max Weight is you should still have it weighed (if only to find out how much Wine you can carry!)