Purchase the correct door, plane to size, chisel out hinge rebates, chisel out mortice for lock, chisel out lockplate rebate, drill out hole for handle shaft, drill out keyhole if needed, attach hinges, hang door, fit lock, fit door furniture.
Sorry, but information is not the same as knowledge.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix windows and doors.