The entire answer is pretty much summed up in this, love your neighbour as yourself...
don't be a stumbling block for guys (or girls who struggle with their sexuality.)
Basically, why are. you wearing what you are wearing? Is it motivated by love for your brothers and sisters? Does it honour God or does it draw attention to your figure? Does it expose thighs, bum and chest? Does it cling to them? Does it expose flesh around those areas? it is probably going to make the majority of men struggle with their thoughts, even believing men. If it makes a father feel uncomfortable, it is probably because he knows how guys think and doesn't want them to think that way about you.
It is hard because of the media and our society. The whole idea that women can wear what they like and men should simply just stop leering at them is not biblical. Sure they need to be self controlled, but even David who had a heart after Gods own heart fought with his eyes to not look at women in a day when they all wore baggy shapeless robes most of the time... how do you think he would have handled hot pants and crop tops!
The reason they sell is primarily because they are "sexy", and society is full of over sexualisation so it has been totally normalised, to the point they buy t-shirts for their little girls that say things like "so many boys but so little time"! It is considered cute or funny, when in reality it is neither. It is sick.
You can dress nicely without compromising, just above the knee is safest, but check how it fits when you sit or bend too as often things ride right up, check tops dont fall open when you bend over, dont wear clothes that look like you sprayed it on your body and leave nothing hidden, ask older Christian women who you feel dress nicely but modestly what would be appropriate if you have things you aren't sure about, hopefully they will be honest with you and leave you to make your own mind up.
I used to be so clueless in my teens, but looking back I wore what I wore because I felt it was fashionable and I felt I looked attractive. I did not understand that men mostly designed the clothes I was wearing and it was not because they were good men of God. It was because the media promoted sexy - and so they sold what was popular because it made money, and as we know in this world, sex sells.
I really commend your desire to be pleasing to God, it is a journey and I am sure you will progress well if your attitude stays this way