Minor with 1099 r

She would claim the standard deduction of $14,600.  This applies to anyone who was a US Citizen and is single and is not itemizing deductions even if they are a minor or claimed on another persons tax return. 

If you are e-filing, you will just put her name on the return.  If you are printing and mailing it, she can sign it.  If for some reason she can't sign it, then you would sign it and add parent for minor child. 

She would complete and file her own tax return, filing as Single.  She would automatically get the Standard Deduction for her filing status.  

However, since you hare claiming her as your dependent on your tax return then she has to indicate on her tax return that she can be claimed as a dependent.  She can sign and date her tax return.

She may get less than the 14,600 Standard Deduction if she doesn't have any earned income from W2 or self employment.     The 2024 Standard Deduction for an individual for whom an exemption can be claimed on another person's tax return is limited to the greater of:

…..the minimum of $1,300 or
…..Your earned income for the year + $450 (but not more than 14,600)

So you would get a minimum of $1,300 to a max of 14,600.

See Table 8 Standard Deduction worksheet for Dependents on page 26
https://www.irs.gov/pub/irs-pdf/p501.pdf

Oh and be sure to check the box on her return that she can be claimed on someone else's return.