I can remember back in the day when I put a piece of vellum on a drawing board I had to consider the size of the item to be drawn vs the size of the paper, figure a scale and then draw it to scale. With the computer age those days are over with. TC draws using a scale of 1:1. When you are ready to print you set the scale with consideration of the drawing size vs the paper size. The computer already knows the drawing size so you select the paper size and scale in "Page Layout".
A custom template can be saved in the 2D or Model-To-Sheet (model is your drawing and sheet is the template) folder depending on its intended use. A 2D template does not have a view where as an MTS template has one or more of them. If your drawings are 3D then the views you may want are top, front, side, and isometric. If your drawing is 2D then a top view is all you need.
If your drawing is 2D only then you can load your template and put a draw view inside the drawing area (the default view is front so change it to top) and set the view scale to 1/24 or 0.042, either one will give you 1/2” = 1’. The view will automaticaly scale the drawing, just be sure the view is active and all the drawing you do is inside the view area. If the view is inactive or you are outside the view the scale will be 1:1. The custom template can be saved as a symbol (but not the view) or in the 2D folder. Templates in the 2D folder are accessed using the "New Using Wizard" then selecting 2D Templates in the dropdown window.
I think I could give you more focused advice if I understood your intended workflow and printing requirements.