How shuffling becomes real skating: push sideways-backward, then glide on one foot. With clear milestones and the typical mistakes that slow you down.
The honest answer first: real forward skating means alternately pushing off and gliding on the other blade, instead of shuffling. In the learn-to-skate curricula, forward stroking comes roughly in the middle of the beginner levels, after marching, two-foot gliding and one-foot gliding [1][2]. That is realistically achievable, but it needs repetition and is nothing for the first afternoon.
Why is it different from walking? When you walk, you push the foot straight back. On ice the blade just slides away. The blade moves you forward when you push it away at an angle, sideways and backward. Then you roll on the other foot. A comparison from the ice hockey lab shows the principle: on acceleration the ankle extensors deliver a lot of force, at speed the knee extensors take over and the leg swings out further sideways [3]. These numbers come from hockey players, not recreational skaters. The principle applies to you just the same.
Walk forward on the ice, toes slightly turned out, knees and ankles slightly bent, chest and head up, arms slightly in front of the body and parallel to the ice [1]. Start with small steps.
After three to four steps hold a two-foot glide for about three counts [1]. Milestone: you manage this ten times in a row without wobbling.
Push a little harder with each step; that brings speed and confidence [1]. At push-off the blade points slightly outward. You push sideways-backward, not straight back. A helpful thought is to look at the effect, not at your body: "I push the ice away", instead of "I extend the knee". In a meta-analysis with 566 participants, people using such an external focus learned sport skills better than with a body focus; the studies were small and prone to bias, though [4].
After the push you glide on one foot. The other is held briefly in the air or close to the standing leg. The weight is over the standing blade. The goal in the curricula: at least three counts on one foot or glide as far as you are tall [1]. Milestone: you roll out three counts on the right and on the left.
Now you alternate: push, glide, push, glide, a whole rink length, eyes ahead. Over time the distances get longer and the strokes calmer. The curricula ask here for "forward stroking using the blade properly" [2], that is, using the blade sensibly, not just speed.
Film yourself from the side, ideally over one rink length. Look at three things: are knees and ankles bent at push-off? Does the pushing foot point slightly outward at the end instead of straight back? And do you roll at least three counts after the push before the other foot touches down again? If two of the three points are right, you are on the right track. The video also shows whether your upper body stays calm or sways with every stroke (experience, not a study).
Skate with the flow and keep your distance. With more speed on acceleration the risk of falling increases. Wear a helmet and, when in doubt, let yourself fall sideways (see the guide "Falling and Getting Up on the Ice"). This guide explains and motivates, it does not replace supervised training, especially if you feel unsure.
Try the counting rule: count out loud until the blade has really rolled out. Anyone who counts honestly notices at once whether they glide or just shuffle. If you get from three to five counts, you skate much rounder. Make it a game: how far do you roll to the next rink marking without an intermediate step?
In stages: first marching, then two-foot gliding, then one-foot gliding, then alternating with a firmer push [1][2]. After three or four steps make a two-foot glide for three counts and push a little harder with each step.
Usually because you push straight back as in walking and the blade slips. Turn the foot slightly outward and push at an angle sideways [1]. Stay low with bent knees, since straight legs deliver hardly any power.
That is very individual. We cannot back a fixed period. As a guide, use the milestone: if you glide three counts after four steps ten times in a row, you are ready for rolling out on one foot (experience, not a study).
On acceleration the calf muscles work hard, at speed the thigh extensors [3]. That comes from a study of hockey players, but it shows why you should skate low and bent.
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