This can easily be completed on the tutorial map.
After completing/skipping the tutorial, head up the stairs. Here is what you need to do:
For 3 milks buckets: After heading up the cobblestone stairs, enter the room to your right with brewing stands in it. Access the chest on the right and take out an iron pickaxe.
Now leave the building and turn right and walk towards the large building where you will see some with the pumpkins and 4 iron blocks. Mine the iron blocks with your pickaxe.
Take these blocks to a crafting table, and break them down into ingots. Now create some 3 buckets.
Head down the stairs opposite the building and you will see a bunch of cows in a pen, simply LT on them with your buckets to fill them.
For eggs: Right next to the cows will be a pen full of chickens, if they haven't laid any eggs yet, simply do the other steps and come back.
For 3 wheat: Across from the animal pens is a farm, take 3 wheat from there.
For 2 sugar: You'll need to find sugarcane. I found mine near the water behind the sand buildings in the town. Craft the sugarcane into sugar and your good to go.
Surgarcane can be found at the following coordinates on your map: x:73 Y:64 Z:184
(thanks to nikon82uk for this information)
Now take all the ingredients and go to the food tab of the crafting table and make a cake.