Assalamu alaikom wa rahmatulLahi wa barakatuhu,
The following may help you with the first and second question.
First of all, we muslims obey Allah without hesitation. We hear and obey. Then comes the questions, why, how... These questions must never be out of rejection or to deny something that we just didn't like.
Any muslim has many duties, things to do and things to never do, before doing anything in your life, from the smallest to the most important thing, you have to consider Islam and if it is ok to do that thing or not, you have to know if it is haram (forbidden), halal (allowed), makrouh, mustahab...
if you don't know ask someone with good knowledge of Shariaa (+/- Islam rules).
If you still can't find an answer when you confront some situation, try to think what Muhammad Sallah Allah Alaihi wa Sallam would do if he was in your place, knowing that he is the ideal human.
Allah created us and put brains in our heads, if a honest person thinks rationally and begins to analyze this world then that person will follows primitively what could is right and refuse what is wrong and that will lead him to Allah (which I think most of the converts did).
If you believe That Allah created you, then who else do you want to tell you how to live ? Allah created us and knows our limitations, He ordered us to do doable things. If not, then He would be unfair (Almighty Allah subhanahu wa taala). Your reasoning should never come across things that destroy the meaning of Allah existence and unity, like saying He sleeps, eats... it will not make sense if Allah sleeps, eats, if He has a wife or son, if He is unfair, if He lies, Allah doesn't wonder, He knew and knows everything along the infinite time. Those are few things from Akidah (+/- doctrine) that every muslim has understand
When we obey Allah, our deed will not add anything to Allah. If we disobey, it will never harm or take something from Allah, nothing will do.
Everything that exist beside Allah is created by Allah thus everything needs HIM to sustain its existence AND HE needs NOTHING.
Because He doesn't need anything, HE is worthy to be worshipped.
Then, before asking why the hijab, everyone should understand that it is made for everyone's sake. If The One Who created us told us that we need it then we do need it to live.
This life is a trial, a test that we all should pass. Allah sent his prophets and gave us his message, the Coran. Because we need the Coran and Sunnah to pass this test, to go to heaven where there is the reward.
I just remembered a hadeeth meaning that the heaven is surrounded by tiring things like (+/- hard duties, like waking up for fajr or fasting a whole month and ...) and the hell is surrounded by desires.
We do not see what lies behind them.
As a man, I see each woman who wears hijab an untouchable queen, I can't even cross my eyes with her. Why can't I look at her, why doesn't she show me her hair or skin ? Because she does it for someone else, her husband or her brother can see her hair, those people are close family. The respect and pride the woman get from wearing hijab is really great, the woman can say : I don't shake hands with strangers, Oh ! You are my cousin, so what ! you can't see my hair, who are you to come this close, it is forbidden, only my husband can touch me.
I am sure such woman will feel secure, proud, happy and closer to Allah because she followed what He told her to do. And for her husband to be in such happiness and luck that his wife is protected in society...thanks to Allah.
A simple example that may help to understand our limitations when it comes to think about Allah ;
A person made something, a table or a car. Can that car understand or comprehend something about that person !? inconceivable, right?
We couldn't fully understand the human body which is something we can see and touch, we are powerless in front of nature, space... still ignorant about millions of things yet we try to understand things we shouldn't tire ourselves with.
If someone claims he understands everything about Allah, he lies because it will coincide with the principle that a creature can never get full-knowledge of the creator.
Assalamu alaikom wa rahmatulLahi wa barakatuhu.
I don't know for the last one- sorry sis!!!!!!
