Shtark girl, questions are always important to ask even if the answers are clear-cut.
You can’t have a mother putting on teffilin while the baby is crying, you can’t cook dinner and leave little kids at home while running out to shul to daven. Even though you are still a girl I’m sure you understand why it wouldn’t work for women to have mitzvas that are time-bound. I’m sure when you’ll be older you’ll understand it even better. Hashem created this world and in His infinite wisdom gave the different mitzvos to men and women in the capacity that they can fulfill. The answer why women werent commanded to do timebound mitzvos is clear.
Part of asking questions is gaining an understanding where the questions stem from. Questions that make a person feel bitter that they can’t have something that’s not for them stems from the yetzer hora. We all have a yetzer hora, as long as we live we should be growing into better people so there’s nothing wrong in exploring why we feel the way we do. But the fact is that if we get stuck with the mindset of why we can’t have things the way we think it should be then we can never be happy. Accepting and appreciating the way Hashem has created us and what He has given us is the #1 key to happiness.