The error message is fairly explanatory, but I can imagine that it could be confusing if you don't understand some of the terminology. Usually, it is a good idea to do a search in the documentation if you don't understand any of the terms used.
In your case, the Check Signal Attributes has been used to ensure that the input being fed in is a frame-based signal, So, you need to give it a frame-based signal to resolve the error.
