Here’s one example: How to do "Prismatic" Lettering
Another: Setting text (or insetting it)
Get what you can from those, or do a search & see what else you can find.
If you still have questions (I had a lot!!) come back and ask. It really helps if you know what kind of project you want to do. Dimensions, Text style, the stock you will use, the tools you have to cut with…
Bar napkin sketches are great, it doesn’t have to be detailed machining drawings. 