I put down that I was not a dependent to anyone, but my Father listed me as a dependent because I still live at home. Can I undo my choice on that?

[xmasbaby0]

..."I still live at home..."     Provide some details.  That you still live at home is not enough information.  How old were you at the end of 2022?  Were you a full-time student in 2022?   Did you have less than $4400 of income in 2022?

Do you fit the criteria to be a qualifying child or a qualifying relative?   If so, then change the way you answered the question in My Info when it asks if you can be claimed.

WHO CAN I CLAIM AS A DEPENDENT?

You can claim a child, relative, friend, or fiancé (etc.) as a dependent on your 2022 taxes as long as they meet the following requirements:

Qualifying child

• They're related to you.
• They aren't claimed as a dependent by someone else.
• They're a U.S. citizen, resident alien, national, or a Canadian or Mexican resident.
• They aren’t filing a joint return with their spouse.
• They're under the age of 19 (or 24 for full-time students).
• No age limit for permanently and totally disabled children.
• They lived with you for more than half the year (exceptions apply).
• They didn't provide more than half of their own support for the year.

Qualifying relative

• They don't have to be related to you (despite the name).
• They aren't claimed as a dependent by someone else.
• They're a U.S. citizen, resident alien, national, or a Canadian or Mexican resident.
• They aren’t filing a joint return with their spouse.
• They lived with you the entire year (exceptions apply).
• They made less than $4,400 in 2022.
• You provided more than half of their financial support.

[Hal_Al]

Q. Can I undo my choice on that?

What is the status of your return and your father's.  Have they both already  been filed.  Was your e-file rejected. 

If your return hasn't been accepted, go back to the personal info section and click edit next to your name. You will eventually be asked if someone can claim you as a dependent.

As the other reply indicated, you and your father need to review the dependent rules to see if your qualify as a dependent.  There are two types of dependents, "Qualifying Children"(QC) and Other ("Qualifying Relative" in IRS parlance even though they don't have to actually be related). There is no income limit for a QC but there is an age limit, student status, a relationship test and residence test.  

The support test is different for each type. The support test, for a QC, is only that the child didn't provide more than half his own support. The support test for a Qualifying Relative is that the taxpayer provided more than half the relative's support.

With the tax law change, effective 2018, most dependents, with earned income or scholarship income,  will get the same refund whether they claim themselves or not. The personal exemption has been eliminated and the standard deduction increased. However, you only qualify for an education credit, if you are not a dependent. Even then there are limits on the refundable portion of the ed credit.