Skullgirls is definitely not a game that someone can kinda just pick-up and get good at immediately without prior experience, but at the same time it also shouldn’t stop you from playing either. There’s kinda a curve with difficulty in fighting games, and once you climb that curve things begin to start making sense.
For starters, play the tutorials. Not all of them you’ll probably complete/understand at first (believe me, I once struggled with blocking mix-ups too) but start with the basics and keep putting effort in. From there, you can use what you learned there in training. Try all the characters (or just pick one that looks cool) and learn about their playstyles.
Like what Svierrod said, blocking and reaction time are probably some of the most important fundamentals in a fighting game. Once you nail those you can start getting the hang of learning to punish dropped combos. Combos are something you should definitely learn, but it definitely takes a bit to get the hang of. Start with basic neutral combos, like maybe this combo with Filia:
LP -> MP -> Hairball
This will kinda train you to start learning how to chain neutrals (normal button presses) with supers (the fancy command stuff). You can also try chaining neutrals with blockbusters too for extra damage. That’s gonna be a necessity in matches.
A good way to practice is to play arcade mode with a character you like. Arcade mode gives you a good mix of all the characters, so you can learn each ones strengths and weaknesses. Start with the easiest difficulty, and once you’ve feel like you’ve mastered it, move on to the next difficulty. It’s a matter of time before you figure things out a bit more!
More importantly, don’t be afraid to pop into training mode every now and then. Training mode is what the name suggests, so just pick a character you like and mess around with them. See what you think! All the settings it has are a
little intimidating if you don’t play fighting games, so you’ll probably just wanna start by leaving them off for now. Once you get more accustomed to the game though, try messing around with features like hit-boxes.
That’s about all the advice I can give. Eventually once you nail all the basics, you can start getting into more advanced territory. Being honest, you’re gonna have to be prepared to get beat. A lot. Fighting games give you lessons that way and sometimes it’s gonna piss you off lol. Take a break every now and then, cool off if you feel like you’re about to throw a controller in the wall. But, as long as you enjoy playing the game, you’ll get better without even noticing.