The limit is the number of words you can physically store. When @AlexK made his What’s My Word? Wordle clone, he included over 2000 words, and that’s only the 5 letter words! You would run out of space eventually.
No you can’t “import OpenAI”. You have to pay to use all those APIs, so if you’re willing to pay up then be my guest. And they are pay-per-use, so every time someone played your game it would cost you money.