it all depends on the provided. some will source the parts if you ask them. or its normally cheaper to just have a bare PCB made and add the bits yourself
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Are you wanting a 2 (or more) layer circuit board etched with solder mask, or are you wanting the same with all Surface mount devices already soldered onto the design?
The first is any PCB Service. The second is many of those An Example. Referred as Full Service / Placed Boards.
The prices are very, very high if you are making less than a dozen, and don't come down into "reasonable" price per board until you are over 1000 in qty.
Each board house is different, and will order the parts you spec, or available substitute. The more picky you are, the higher the price goes.