Spoiler means it moves up which= less lift and more drag
Flaps means it moves down so it= More lift and more drag
use flaps to mantain low speed without stalling so you can approach the runway, once you touch down deploy the spoilers to keep yourself on the ground and slow down, if you really need to go down quickly without going super fast, spoilers are your friends, if you are stalling put full thrust, put nose down and deploy flaps to gain more lift, if you need to take off in a short runway, flpas will help you be able to take off at lower speeds.
Hope I helped