Practically speaking: no. You can't always prove that your text was used to train the AI unless the AI spits it out verbatim.<p>Legally speaking: we don't know yet. This issue is only just starting to work its way through US courts.
In the US at least, you don't need a license to protect your work, you get it by default. You retain full ownership and copyright of any creative works that you author. Nobody can use your work in any way without permission, with exceptions for fair use.<p>Whether you can afford to defend those rights is another question entirely.