I went ahead a read all three. I'll give feedback by episode, but I'll start with the summary. The summary It could be a lot shorter, It has a lot of redundancies. I think someone like this would be better:
Summary
The life of the twin sisters Selena and Elena had always been pretty normal, but that simple life instantly changed when they discovered they both had magic powers. Now they'll have to find a balance between their normal lives and fighting monsters, ghosts and evil witches, but not without the guidance of a lovely witch named Crimson Shine who works for a mysterious organization that protects humanity from supernatural threats.
Episode 1
I'll start with the positives. The the flashback to the robbery was very well done. It pulled me into the story immediately, and the action was a highlight. It shows a lot of potential. Also, I love the last page. It's a simple but effective touch letting us know the fate of the poor store clerk. I was kinda shocked that he just got shot moments after he was introduced, so I'm glad he's okay.
I get what you were trying to do with the opening of the episode, but between the summary and the opening the word "normal" nearly lost all meaning. I found the intro to be kind of dull, I only became invested in the story when the flashback happened. Maybe you could consider starting off with the flashback, or with the girls entering the house. It would be a much stronger hook.
You do have some minor grammar mistakes, but it was nothing too serious. It could bother other people more, but It didn't hinder my reading or take away from your story in my opinion.
Episode 2
The positives: There were a lot of things that made me laugh this episode.
You have a tendency to give the same information more than once and it's unnecessary, especially within the same episode. For example, you don't have to say their mother wasn't pleased with them leaving to fight in the intro, because you showed that very well later on in the episode. And it was much more interesting seeing their mother's reaction than reading a block of text about it, especially when it's followed by more exposition in the following panels.
The same thing applies to mention of the organization in the beginning. While brief, it was also unnecessary. You could just say her name is Crimson Shine, and she along with Smiley belong to an organization. Later on in the flashback you already give the full name of the organization, along with some background. In fact, you don't even have to mention the organization at all in the beginning of the episode. You could just give us Crimson and Smiley's names and leave it at that until the flashback where it's explained.
It's not very interesting reading the same information over and over again. When you're doing your script, try to keep an eye out for it from now on.
edit: since you explain magic and talents the very next chapter, there's no need to go into any detail about it in this chapter. You can just say "...we, the witches, need to study and learn in order to use magic..." a.) "outside of our 'talents'..." b.) "beside our 'talents'..." or you can phrase it someone other way, these are just examples.
Episode 3
positives: Good action, good humour, and I like the foreshadowing at the end
Honestly Selena was me in the beginning of this chapter. My eyes glazed right over when I saw all that text, and I skipped right past it. It really was an info dump. How important to the story, and our understanding of the story is that information? If we didn't know half of that, how confused would be be? And, are there other ways you could give us that information? I would give the information that is important to our understand of the next few episodes first, and then give the rest as it becomes relevant. If it's just world building, then maybe just give us one piece at a time as a fun fact at the end of episodes.