Any information or document that you upload to a GenAI tool might get shared in answers to other people, or it may be used in the GenAIs training data.
You would be in breach of copyright law if you upload:
Basically, only upload data that is openly available online, or your own information such as prompts.
Be aware that if you upload your own work, it could also be shared or used.
If in doubt check the GenAI tools terms and conditions, but these may change, so always check them before you upload anything that you are unsure about.