1. At least one Tavern/alewife
2. The Village Green (common land for grazing, also used as a marketplace or festival area)
3. a few cottages for the farmworkers who work on the local lords land (These buildings would be 1 or 2 room dwellings, with their own vegetable gardens)
4. A church/temple
5. Blacksmith
6. a few "material specialists" (hunters, woodcutters, charcoal makers, maybe miners or quarry workers?).
7. A source of water (well? stream? river?)
8. The local manor house with associated buildings: stables, tithe barn and storehouse
9. An inn and an alms house (if the local lord and/or temple is generous)
10. A mill
How realistic do you want to be? For example, most Fantasy RPGs tend to ignore the absence of indoor toilets. Most of the cottagers have to defecate into a wooden bucket and can be seen "slopping out" each morning at the river/stream. A great time to catch up on the local gossip and develop a wide range of diseases!
Personally, I find it helps to think of WHY the village is located in this particular place. This gives an idea of the important buildings.
For example...
Is it on a good road and about 1 day's travel from a town? Then think of it like a Motorway Service Station. It could be built up around the inn and stables. Your local specialists might include a wheelwright, suppliers of "fast food" and a few entertainers. If the area is dangerous, there should be a defensive wall around the place.
Is the village built where the river narrows or becomes too shallow? Then you have a riverport. You need a place where people and/or cargo can be transferred from road to river. The place is built around a fortified storehouse and (possibly) a barracks and custom house. Craftsmen will include coopers (barrel makers)
Is it purely a farming village? Then you need a place for grain to be stored and/or dried. A baker and a brewery are likely. The local lord will have control over the mill and expect taxes to be paid in grain and service.
