New Manager, Going crazy

It's me, I'm the new manager about to lose her mind. I was highly qualified for the position, and I'm very thankful to have gotten it, BUT I just feel like I'm in a terrible spot with my employees (or something).

I work at a grocery store and I manage the front end. This means I look over the cashiers and cart pushers. Most of my cart pushers are high school kids and they almost always show up to work. The cashiers?? Problem after problem. I have some that call in everyday for days, never want to go to the doctor to get a doctor excuse. I have one who wants to take every holiday off and even if she is scheduled she will not show up. This person then offers to "work 10 hour days" to make up for her hours. I do not care about how many hours you make, it has to do with being at work when I need you there! I have one lady, in her 50s, she says she needs 40 hours. Then she complains if she doesn't get at least one weekend day off and calls in during the week as well. One of them works two jobs, she wants me to schedule her 4 to 5 days a week, but when I do that she calls in many times because she's overwhelmed. Not to mention, multiple people quitting for no known reason, which I know I cannot control.

I feel like I am all over the place with this post. I mostly just wanted to be able to vent and possibly get some feedback from people in my position or who have been there before. I just feel like I'm trying as hard as I can, but these people do not work with me at all. I'm just wondering how do people like this live and pay bills when they never come to their job?????