My parent's tax preparer wrongfully claimed me as a dependent. They are amending their tax return to remove me as a dependent. Must I file by mail now? If so, do I need to wait until the amendment is processed or am I able to mail now? Thank you.
No, you do not need to wait for the amended return to process. That will take 20 weeks or longer.
You can print and mail your tax return now. The IRS will process your tax return normally without regard to the other tax return that was filed.
The question on your return is "can" someone claim you as a dependent. It doesn't matter whether that they do not. you provided no info on why your parents can't claim you.
you can use IRS tool to check.
https://www.irs.gov/help/ita/whom-may-i-claim-as-a-dependent
If your parents can claim you as a dependent, but chose not to, you have to change your tax return to say that someone can claim you as a dependent. You will then be able to e-file immediately.
If your parents cannot claim you as a dependent, you will have to file by mail. You do not have to wait. Even after your parents' amended return has been processed, you will not be able to e-file this year.