Your daughter should file a form W-4 for federal income tax withholding and a form MW507 for state tax withholding. Just read the form and follow the instructions. I can't explain everything, but if you have a specific question after reading the instructions, someone may point you in the right direction.
Just be aware the form is several pages of instructions, not just the bottom half that gets turned in to the employer.
https://www.marylandcomptroller.gov/content/dam/mdcomp/tax/forms/2025/MW507.pdf
https://www.irs.gov/pub/irs-pdf/fw4.pdf
In most cases, the fact that your daughter works does not affect your ability to claim her as a dependent. Only if she earns so much that she pays for more than half her living expenses. That includes her clothing, travel, entertainment, medical expenses, and a percentage of your home expenses like rent or mortgage payment, food, utilities and insurance. It is very uncommon for a child to pay more than half their expenses. And what counts is what she pays for, not what she earns. If she was a child actor making a million dollars a year, and saved it all, and you paid the daily living expenses for the family, then she would still qualify as a dependent.
All the rules are in publication 501, and Turbotax also has an interview that will ask the questions needed to determine her status.
https://www.irs.gov/forms-pubs/about-publication-501
