If you’re US based, the best and really only option is a full sheet set including fitted sheet, flat sheet, 2 pillows per person per bed, and either a duvet with duvet cover or 2 additional blankets as top blankets. Blankets, sheets, pillow cases, and duvet cover get washed every time. Duvets get washed periodically (depends on occupancy) or if they display stains/dirt. Decent synthetic fill duvets are not difficult to wash and dry, but do take up a whole load so definitely extend the process. On top of that get waterproof cases for your box spring, mattress, and pillows. These get washed frequently (except the box spring) but not necessarily every time unless stained. In my case, keeping everything white keeps things easy and, more importantly, looking clean when they ARE clean. In Europe and other countries I’ve noticed the norms for bedding are different, particularly lack of top sheet with only duvet/cover. More on reddit.com

You have the fitted sheet that goes on the bed to protect it from your sweat and oils. You then have the top sheet that goes over you to protect your blankets from your sweat and oils. You then have however many blankets, quilts, and comforters you want to use. I have never heard of a bed cover and do not know what that product is. It is either you misnaming the top sheet, or it is a decorative cover put on beds to protect them from dust. More on reddit.com

Let's start with a bare mattress and work up to a fully made bed.

You start with the optional mattress cover. These come in a variety of styles, thicknesses and purposes. Some are waterproof (which protect the mattress from accidents and spills which can result in mold growth).

Next is a sheet set. There are 2 pieces in the sheet sets (not counting pillow cases). One is a fitted sheet which goes either directly on the mattress or over the mattress cover then over the mattress. This piece has elastic at the sides to keep it tucked in place around the mattress corners.

The second piece is a flat or straight sheet. This gets tucked in at the bottom corners but not at the top usually. When you get into bed it is generally between the two sheet pieces with the flat sheet acting as a light blanket. (sheet sets are generally easier to launder than blankets, comforters, duvets...) so the flat sheet acts as a barrier between you and the more bulky bedding keeping you warm at night.

As fr blankets there are many types. Throw blankets are generally what is used when sitting on a couch or as a decorative accent on a bed (which also means you can take a nap on the bed without unmaking the whole bed).

Duvets are generally a basic plain shell stuffed with different kinds of materials (some are down or feather filled, others are stuffed with a polyester type filling, and there are other options as well). They generally have different thicknesses and materials that are well suited for different temperatures. It's common to also buy a cover for this type of blanket both as something to keep the blanket itself cleaner (as the cover comes off and is easy to clean and dry) and as a decorative touch.

A quilt is a blanket that is pieced together (usually only on one layer as patchwork) and sandwiched with a backing and layer of batting (which is a sheet of material that gives the quilt it's warmth). The word quilt refers to this layering and sewing together to make a blanket. It differs from a duvet in the material used between layers and how they are held together. A duvet generally has loose filling that can shift throught the blanket or in larger parts of the blanket while a quilt has more stable material between the layers that doesn't move or shift or need to be fluffed. The quilt doesn't get a cover because the patchwork top is generally the decoration itself.

A comforter is a bit of a cross between a duvet and quilt. It can be stable or loose filling, does not need a cover and is generally sectioned to keep the material from shifting too much.

Generally most people choose between one or the other of these blankets, though it's not uncommon in areas with wide ranges in temperatures to have bedding sets to accommodate different seasons.

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If I'm not mistaken your describing the system used at better hotels.

One sheet goes on the mattress and is tucked under the mattress ... It's the bottom layer your body sleeps on.

The next flat sheet is put on the bed With the top of the sheet even with the top of the mattress

The duvet/comforter is thrown on next, just like the previous sheet.

Now one more sheet is thrown over that. The top three layers are now folded over about two thirds of the way up.... and the pillows are placed where the head would go.

That's the type of fold down service I've had at the four seasons and better 4 star hotels.

I liked it so much I switched to it myself. You don't even need a duvet cover .... Just the down comforter in between two sheets.

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