Uhoh---did you try to use the online software to prepare a tax return for some other year? Is that why you are looking for a way to "check" a different year? You cannot do that. The online program is ONLY for a 2019 return, and cannot be used for any other year. There is no way to check a different year. So.....if that is what you did you have used the wrong software. Do not try to file the return--it will be all wrong.
Post back and tell us what you did so we know how to help you out of a mess.