First of all, welcome to TomTomForums.
"Exactly the same" is of course not possible. (One-way streets, the other side of a roundabout, etc.)
Unless you make changes in the Settings, TomTom is designed to get you the fastest from your "current location" to your destination.
(When your GPS has a satellite fix, the arrow/chevron on the map will be blue and that is the current location. If your are in a house it may be blue but in a flat it will most likely be grey until you are out in the open.)
You can set waypoints (stop overs, with or without actually stopping) if you want to drive a particular route.
Lets say you want to go to Northampton but via Luton and Bedford. You would use Northampton as your destination and you sue the other two as waypoints.
If you now want to go to home it will most likely select A43/A421/M40/+ as the fastest route.
Please let us know what you have in mind as there is a way to drive the opposite direction as the outbound route.
For my taste it is too involved and I do not bother with it but others here will reply to you too and the more they know about your intentions, the better they will be able to advise you.