Since the 1st of March 2020, public transport is free in Luxembourg, so no need to pay for a ticket.
There are 4 bus stations, which are very near:
The line numbers, which come to one of the 4 bus stations are:
You can use Mobiliteit.lu to get the timings.
The nearest tram station is Limpertsberg, Theater (Tram). From here you can take a tram to the Kirchberg Luxexpo or to the main train station (Gare Central).
Parking spots are available in front of the building with 132 spots and many more in the adjacent streets.
There are two Carloh stations right in front of the building on the big parking lot.
Nothing fancy to lock your ride on. Just bring it with you inside and put it against the wall on the ground floor. (Don't obstruct any emergency exits.)
An invention from the late 70ies called: walking.