You can be subject to kiddie tax (Form 8615) even if no one can claim you as a dependent. Being someone's dependent is not one of the conditions for the kiddie tax.
Are you a U.S. citizen or resident alien? If you are a nonresident alien, you cannot use TurboTax.
The IRS apparently never considered the possibility of a someone being required to file Form 8615 whose parents are foreign. They do not provide any instructions or guidance for this situation. I don't have a good answer for you. If you are subject to kiddie tax, you cannot e-file your tax return if your parents do not file a U.S. tax return.
The best suggestion I can give you is the following. When TurboTax asks whether your parents are filing a joint tax return, answer Yes, even though they aren't. When it asks for your parents' taxable income, enter zero. That is true, since they have no U.S. taxable income. Leave all the other income questions blank. Also leave your parent's Social Security Number blank. When the error check tells you that the SSN must be entered, just click Continue. You will not be able to e-file. Print the tax return. In the space for the parent's Social Security number on Form 8615, write NRA (for NonResident Alien). File the return by mail. Doing it this way will make the kiddie tax zero.
I really appreciate it.
Yes, I am American. But my parents aren't
Unfortunately, I am abroad at the moment so I won't be able to file my taxes by mail.
Do you have any idea if anything can be done to e-file my taxes?
Unfortunately there is no way to e-file your tax return. The IRS will not accept the e-file without a parent's Social Security number.
Why can't you file by mail? It might be inconvenient, slow, and cost a few dollars, but surely there is mail service to the United States from whatever country you are in.
If it helps, you can get a 6-month extension, until October 15, of time to file your tax return. If you have a payment due, you still have to pay the tax by April 15. You can file the extension online and pay online even if you are filing by mail.
(There is an automatic 2-month extension, to June 15, if you are living and working (or studying?) outside the U.S. on April 15, but it's not clear to me that you would qualify for that. It sounds like you are visiting or traveling, not living abroad.)