Salam dear sister, well God (swt) has always commanded his female followers to cover up, it is in the Torah, Bible, and Quran. Muslims are the ones who follow their religion correctly however. Those women who are doing things that are not healthy in this life and will not benefit them at all in the hereafter; they have become pawns of Satan, while you are still guided. You are jealous of the sins they make when they should be jealous of you for being modest and doing good deeds.
The simple answer is, Allah (Swt) commands it in the Noble Quran that women wear hijab: headscarf and loose clothing, hadith states that women can only show their face and hands. You are not dressing modestly unless you fulfill all these requirements. Women who do not dress modestly as described above are sinning on a daily basis for disobeying Allah (Swt) and not wearing headscarf or dressing in tight clothing. They also partake in the sin of every man or woman who objectifies them since we are also commanded to lower our gaze. It is an easy way to rack up sins. Dressing modestly however, grants you a good deed (multiplied as Allah (swt) wishes, depending on how difficult it is for you to wear and dress modestly).
The wisdom behind it is so you don't attract men who only want you for your body, you will attract a Muslim man who wants you for your beauty inside not outside. You should go to the mosque and find a pious Muslim man to marry there and forget drugs, partying, alcohol, fornication, etc. I can only think of one good things these things give you, and that is a good feeling, that's about it, a temporary good feeling, but I can think of hundreds of bad things that come from these things: std, unexpected child birth, holes in your brain, cancer mutations, alcohol itself will lead you to commit many other crimes and sins and impair your judgment, and once you start on this path it is hard to reverse, these are addictions. There is many other things, many other wisdoms behind it, so obey Allah (swt), he knows best, this life is temporary, do not be deceived by it, paradise is the goal.
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