I am sure there is something on the web, but it is very simple
1) create two brand new databases
2) Use a naming convention so you know which is front end and back
Backend gets just the tables. Front end gets a link to those tables and all other forms, reports, queries and code.
3) Open the backend and use the import external data feature to import in all the tables. (you are done with the backend)
4) Open the front and use the import external data feature but this time choose link to the backend tables. If you did that correct the tables showing in the front end should have little arrow icons showing that they are links.
5) Make sure to do 4 first. Now do step 4 again but this time import all the other queries, forms, reports and code.
You are done
You can only modify tables in the backend, not possible from the front end.
6) If you move the backend, rename it, change folder location you will have to relink that backend tables.