How to predict with the ML model I created? (receiving Error)

Hi,

About the different number of sentences, it’s just because I added more sentences in to test out how good the model is in predicting :)) The model was able to predict the CNN news but couldn’t predict the short sentences like “Jack scored 2 goals tonight at New York Stadium”. Maybe the problem was not with the model but its acurracy is only high if the input is long enough? And could you pls help me with another issue at Why shift 370 time steps and not let say 365 time steps??

Thank you so much for always supporting my questions!!