https://www.modelbuildings.org/railroad-structures This short video shows the techniques for building a model railroad station using scrap pieces of cardboard (you can use foam core or core flute instead). For this demo the model train station is constructed in OO scale although it is easy to scale it to HO scale or even N scale if you want. Model railroad buildings really add to the realism and character of the scenery on a model railroad layout, and this scale model train station looks very interesting when constructed as it has an interesting roof line and includes a waiting room, ticket office and restrooms.
Have fun building this model train station. I hope you find the video helpful!