I have so many questions about namaz and wouzou,

1) I heard that, when we make wouzou, and we don’t finished the massa of our feet, we can’t walk or move more than 3 steps. Is it true?

2) If I do mistake in the zikr for example, Do I have the right to just correct it directly? Or I have to re do my namaz again?

3) Moreover, if I am performing my namaz, my clothes slide, so we can see , the part of my body that Its wajib to cover (example my wrists) , do I have to re do my salat? Or just cover it again and continue it ?


4) If at the end of my salat, I realize that we can see a bit of my hair, do I have to re do my namaz , or its valid?

5) When I am saying the zikr of my namaz, and accidentally, I make a sound or I speak loudly, Make my salat baatil?

6) After I finished my prayer, I realize that I did a mistake in the Tasbi ate arba , I said ‘subhannallahi…. wa la illaha ILLALAHI…’
instead of ‘ …. wa la illaha ILLALAHOU…’
So , I just re do my namaz to be sure and to not have any doubt.
But know, the problem is that I dont know if I did this mistake or no before . So what do I have to do?
Is this kind of mistake make salaat baatil?

7) When I am doing my wouzou, and my arms just touch or touch something else like my clothes or the door for example, make it invalid ?

8)Then, do you have some advices to be concentrated in salat? I have so many difficulty to be concentrated ..