Dependent

As long as she meets the qualifications, you can claim her.

Qualifying Child

Relationship — the taxpayer’s child or stepchild (whether by blood or adoption), foster child, sibling or step-sibling, or a descendant of one of these.

Residence — has the same principal residence as the taxpayer for more than half the tax year. Exceptions apply, in certain cases, for children of divorced or separated parents, kidnapped children, temporary absences, and for children who were born or died during the year.

Age — must be under the age of 19 at the end of the tax year, or under the age of 24 if a full-time student for at least five months of the year, or be permanently and totally disabled at any time during the year.

Support — did not provide more than one-half of his/her own support for the year.

Qualifying Relative

You can claim a child, relative, friend, fiancé (etc.) as a dependent on your 2021 taxes as long as they meet all of the following requirements :

• You provided more than half of their financial support. More info
• They made less than $4,300 in gross income during 2021 unless they are a qualifying child.
• They live with you or they are related to you. (Your relative must live at your residence all year or be on the list of “relatives who do not live with you” in Publication 501.) 
• They are a U.S. citizen, resident alien, national, or a Canadian or Mexican resident.
• They aren't (or won't be) claimed as a dependent by someone else.
• They aren’t filing a joint return with their spouse.
• You are not being claimed as a dependent on someone else's return

On you 2022 tax return you can claim her as a dependent under the Qualifying Child rules if she meets all the requirements under the rules.

She only needs to file a tax return if she had taxable income from wages on a W-2 and had taxes withheld from the wages to get a refund.  If her wages were less than $12,950 she is not required to file a return.

If she has income from self-employment of $400 or more then she is required to file a tax return.

If she files a tax return make sure that she indicated on her tax return that she can be claimed as a dependent.

To be a Qualifying Child -

1. The child must be your son, daughter, stepchild, foster child, brother, sister, half brother, half sister, stepbrother, stepsister, or a descendant of any of them.
2. The child must be (a) under age 19 at the end of the year, (b) under age 24 at the end of the year and a full-time student or (c) any age and permanently and totally disabled.
3. The child must have lived with you for more than half of the year. Temporary absences while away at college are considered living with you.
4. The child must not have provided more than half of his or her own support for the year.
5. If the child meets the rules to be a qualifying child of more than one person, you must be the person entitled to claim the child as a qualifying child.
6. The child must be a U.S. citizen or U.S., Canada or Mexico resident for some portion of the year.
7. The child must be younger than you unless disabled.