My advice for any fighting game? Once you get the basics of your favorite down, study the frame data to setup whiff-punishes.

If you whiff (miss) a attack, you are minus frames, in other words, slower recovery, and your opponent is plus frames, meaning they can retaliate with you being unable to defend yourself.

Most Netherrealms Games #MortalKombat and #Injustice already give you frame data for free. Tekken 7 paywalls it’s frame data.
There is NO WAY you can make it in #KombatLeague on #MK11 without understanding frame data and whiff-punishing. The fatal blow doesn’t matter, because any skilled player can punish you from full to zero health bar just by a single whiff.