Hello everyone!

I'm new here and also very new to STATA, although I really enjoy statistics. I have several projects in mind and I'm willing to learn some STATA to accomplish them, so I thought this forum would be a good idea.

I'm working with an Excel Workbook which contains information on several past events. My goal is to be able to predict what's going to happen in the future events based on the information I have beforehand, so I take a regression (which I still have to figure out which one is the best). So I import my Excel into stata and execute reg Y X_1 ... X_n , where Y is the variable I want to predict and X_i all the variables I think Y depends of. Once the regression is done, I can execute predict Ypred and STATA will add to my Excel a column titled Ypred which will predict the Y outcome depending on all X_i. Now, here comes my question, what command can I run if I want to know what explicit formula STATA is using to generate the Ypred column? I know I can use the Coef. in the linear case, but not in the others. Is this possible to know?

PS: If anyone knows how can I choose the best regression, any help is appreciated! (I heard about Lasso but don't really get it)

Thanks very much beforehand to everyone.
Daniel