You do not owe your employer for “giving” you a job. They did not create a position for you out of the goodness of their heart. They deemed a set of tasks essential to the continued functioning/profitability of their business, and needed someone to handle those tasks. You are not being given charity and you aren't being done a favor, you are a professional keeping their organization functioning.
You do not owe your employer for training you. If there are specialized systems or procedures at a job that your employer needs you to know in order to function within your hired role, then that training is a time/resource investment that they chose to make. You do not owe them compensation in any form for the time they chose to invest in you.
You do not owe your employer your life. You are not lazy or entitled for taking vacation time. Your PTO is as much a part of the employment package they offered as your salary is. Employers trying to prevent you from using your paid time off are no different than employers trying to get away with paying you a lower-than-advertised wage: they're both trying to withhold the compensation they agreed to pay when you were hired.
You do not owe your employer money. Despite what some sycophants will try to tell you, you do not start out in debt to your employer. From the moment you start working at any job, your employer is in a continuous state of owing you for hours worked until you get paid. In fact, with the way a lot of company's pay periods work, your employer is actually in a state of owing you money for the full duration of your employment. They owe you for the labor and services you provide them, you do not owe them for hiring you.
People can exist without businesses and capitalism, but businesses and capitalism cannot exist without people. If that weren't true, billionaires wouldn't invest so much time and money into preventing labor unions from organizing. Never forget that, and never let anyone convince you otherwise.