See there are no eligibility criteria that are mentioned. So technically your child is eligible for SAT. Now if the student is prepared well then he./she can obviously give the examination and if not prepared then also he/she can give the exam to get the pattern which the examinations asks.

SAT 2021 Subjects

Now if your student knows all this staffs or have taken preparations then he/she obviously can seat for the exam or else I would suggest to have some time i.e., 10+2 and prepare for it. By that time the student will get enough time to prepare as well as no time loss will occur.

You can visit the link below to know more about SAT:

https://studyabroad.careers360.com/articles/sat

I hope my answer helps. All the very best for your future endeavors!