Everyone and everywhere suggest 0.8g to 1g protein per pound of body weight. I am just curious and always like to know why. As long as it is within the TDEE, does the macro matter (not considering extreme case like 100% of the calories comes from fat)? I understand that protein help us retain muscle and repair, what happens if we go beyond 1g protein, let say 1.5g? everyone and everywhere say too much, but why too much?

Firstly, sorry i forgot to tell this in my main post. As I just started to workout, I'm using lightweights that I can handle to perfect my form first and for my muscle to get used to the sudden increase in workload before bumping up the weights.

I'm not sure if after bumping up the weights I can still handle a 3x12 routine. If i can't I'll lower it to 3x10. I have enough weights available at the moment. 2 adjustable dumbbell of 20kg each. I can barely even pick up a 10kg on each side yet.

Next on the meal macros, I planned it like this.

Lean body weight 100lbs. Target calories / day = 2000 calories.

Protein x1.5 = 150g = 600 calories
Fats x 0.5 = 50g = 450 calories
Remaining calories for carbs = 950 calories / 4 = 240g+-

I find protein easier to swallow/eat compared to carbs for my personal taste preference (i love meats and hate carbs) so i did a x1.5 plan since it's easier for me to eat.

However if i lower the protein to x1, should i bump up my carbs or fats?
I don't know what is a push pull split. Can i do it with the equipments i have ready? Thanks for the suggestion though I'll read up on it.
Thanks for the suggestion!