I am moving back to the USA and I've been homeschooled (I'm in the 9th grade), but I was not aware of any credits that were needed to go back into the public schooling system.
First thing I recommend is talking to the school administrators at the public high school you are planning to attend. The transition from homeschooling to public school can vary between states and schools. Be aware that school officials can be unfamiliar with homeschool laws and so the process might not be very straightforward at first.
Each high school has it's own requirements for graduation, and there will likely be some process for you to prove that you've meet certain requirements/credits in your homeschooling. To start, it will be good to be prepared to show records of your homeschool curriculum (if applicable) or any document that shows what you've learned. You also may end up having to take some tests to prove you've learned material required by the school and place into a certain grade.
Having a phone call with the school you're planning to attend will be the best first step! Good luck!
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