I Love Travel.
My Wife and I went Interrailing when we were 25, we only found out about it just before the benefit of being a YOUTH ran out. Rucksacks, tents.

Now we would like to hit BOTH Denmark, Billund and Germany, Günzburg Legoland to take our 18 year old son to BOTH places and visit the factories ( which I am reliably informed is a thing now ).
HERES THE QUESTION.
I am trying to use the planner.
I Live near Southampton (UK), and want to travel by train to Billund ( Yes - that IS a Long trip ), stay a couple of days, and then travel down to Germany, and possibly vists a couple of other places while we are there.
Then travel back to Southampton
I Would LIKE to use the train - since at least I will get a break from Driving for a change.
How do I go about “Starting in Southampton”
Do I choose this as a destination first?
How do I ad. a Starting point - I am confused ( a tiny bit ).
I was thinking that the 5 day Global pass might just about do it - with the two days from UK , leaving 3 days in denmark and Germany. - I Only want to be gone just under a week - as we have cats that will have to be looked after.