@ajatal could you explain which columns are features and confirm what column is the target (Lead time). Then you might want to define what role the date variables might play with regards to what I have said about them.
And maybe you try to comment on the remarks I had about your approach. You will have to think about what information your data might be able to provide.
You could of course just try and build a regression model with your data (without the date variables) and target but it might no help you a great deal until you have sorted out your data preparation.