The schematic or circuitry diagram for any motherboard is proprietary information, not available without special permission.
Best is a specs page about the board, such as..
https://ark.intel.com/products/42408/In ... ard-DH55TCThe owner's manual would have diagrams for pinouts of connectors and power sockets, as well as suggested memory and CPU types.
F@H.. to solve mankind's maladies.. in our lifetimes!