Scaling basically means that you change the intensity of the workout to your fitness level. There is a scaling option for every single exercise. For example, you can always use a lighter weight in a weightlifting session or use elastic bands to help you with pull ups, muscle ups, squats and more, do fewer reps or just anything to help you finish the workout with your skill level.
Even CrossFitters that have been doing the sport for a longer time have to scale occasionally. Perhaps due to injury, or they don’t have enough strength in them that day to keep that weight for a whole WOD.
Scaling can also mean that you do fewer rounds with the same intensity and weights, or just fewer reps of that particular exercise that you have not mastered yet. Maybe the reps for double-unders in the WOD is 50, but you cannot string together more than two. Instead of scaling down to single-unders, which is also an option, you can still practice your double-unders but scale the reps down to 25 or just to doing double-unders for 90 seconds.
For most beginners, scaling is necessary to survive the workout. With time and more CrossFit sessions, you will be able to Rx before you know it. There is no shame in scaling, ask your coach about the scaling options for you.