Is there any time in the early morning on Shabbat in which I can eat and drink something without any question of it being considered eating before davening and kiddush? For example, at 3, 4, or 5 o'clock in the morning? Is there a certain time before netz or alot hashachar in which it's definitely acceptable to eat and drink on Shabbat morning? Also, does the type of food matter? As a second point, what if I wake up early during a weekday? Is there a point at which I can definitely eat and it's not considered eating before davening? is there a point I cannot begin to eat unless I first daven? Is there ever a time at which I'd have to stop eating and drinking and wait until it's time to daven to eat or drink again? Thank you so much for your help.
There are actually 2 variables here in play, one if it shabat or a weekday, and second if the person is a man or a women.
on a weekday a women can eat anything before the morning prayers. for a men it depends, maran says one can drink water, coffee and tea even with sugar while ashkenazim are more lenient on this.
on shabat the same rule applies for man, while for women it depends if she usually prays shaharit on shabat or not.
if yes she can eat the same as men, if not she is already obligated by kidush, therefore you can't eat until you do kidush. note that you don't need to wait, you can do kidush at 7 am and eat your breakfast.
the time for this is the same as the time for praying, all the while it is still night you can eat, as soon morning starts, meaning as soon as the obligation to do shaharit begins you'll need to fulfill your obligations before eating.