I didn’t have complete internet sources when I was your age, but I was mentally out just from certain “unChrist-like” teachings back in the day and I was definitely aware there were other big incongruities and problems. A few of my issues were actually confirmed through studying much later.

Basically, I found one or two like-minded LDS friends my age and we laughed and mocked anything to do with church until I was 18. I honestly think it was a defense mechanism to get me psychologically through it. You can be an influencer or a teacher, but you won’t have any control over your younger siblings choices. Most of my life now doesn’t even revolve around religion. but some part of you will always have tbm relationships to navigate. You are at at a different place now, so don’t give up your beliefs and once you are an adult, commit to following your own life path.