Hi there vivianjackson!
I have an article here for you about enabling closed captions on your iPad:
Specifically, this is the information you seem to be looking for:
You may also want to see the options you have for other settings that can help you use your iPad easier. These options are found in the accessibility settings, and we have an article that explains a host of them, which can be found right here:
Thanks for using the Apple Support Communities!