Book a holiday under 18 with a companion?

Hey people,

My boyfriend and I are planning to go on vacation during the fall break. He is 19 and I am 17, and I will also be 17 on the travel date. We wanted to book with Check 24, and our tour operator would be TUI.
Now we would state that one adult and one child (17 years old) are traveling. My parents also gave me a PDF with the consent form.
Is that enough or do we need more and is it even possible or should we wait until I turn 18?
thanks in advance