I don't want this to sound harsh, but without reading a single word, you can tell there's problems with the script. Just by the way the page looks (meaning : big blocks of text and multiple pages of only dialogue) are already big red flags. They aren't necessarily bad (I mean, Sorkin's stuff sometimes look like that), but I'll tell you what's wrong with them.
You're overloading us with description. Very few people want to read through that.
"The cupboards are handmade from plywood"
Two things that are often drilled into screenwriters are: Write for the screen & every line counts. You wouldn't be able to tell the cupboards are hand made on screen, and more importantly, it doesn't matter. All this detail of Marian's kitchen is fluff. In the end, how this house is decorated will come down to the set designers or director. And most producers don't want to read through big blocks of text.
Get to the story! Get to the conflict! That's what they want to see.
Next, onto the dialogue. It's on-the-nose. Meaning, everyone is always saying exactly what's on their mind, with no hint of subtlety. Dialogue should be more nuanced and more characteristic.
Also, try to avoid telling plot details so blatantly through dialogue.
"If Daddy Martin was alive"
"You're such a smart aleck. Why can't you be more like Phil?"
"I'm not Phil, dammit."
"I think you are crazy."
"I haven't bought anything new since
Daddy Martin died."
"So, Phil is going to graduate with honors, and I'm going to flunk out?"
"I didn't say that." (But she DID say that)
Is this the first time they've had this fight? Do they just always talk about it like this? Are they always so open? Their feelings are so strong, but they're so direct.
All this melodrama brings up a lot of questions because it feels so inauthentic.
This first scene is seven long pages of reptitive dialogue. You're only really hitting two ideas : Phil is the "better" berother and that makes Neal insecure. The second is that Mariam is dating this Al, even though Martin is dead, which also makes Neal uncomfortable.
These two ideas, if done craftily, can be conveyed in less than a page, and partly non visually.
There is something I do like about this scene though. The way Neal uses this "ghost" of Martin as a way to talk to his mother about her situation with Al. To me, that's really clever if he's just playing along or playin on his mother's belief in these ghosts, and using it to find out more information subtlely.
As it is, it's too bland and too long.
The problem is, anyone else is not going to read past those ten pages. Even if you have a good story after that, the first ten pages tell us your writing is simple, melodramatic, and bland. Watching a kid argue with his mom for 7 minutes is not exciting, especially when it's this simple back and forth. I recommend going back and rewriting it. Take out all the lengthy descriptions, and try to encapsulate your dialogue in a couple lines, and more visually if possible.