Well, the picture of the linked device clearly shows it does not do what you want, it says it's a 8-17v input and 20-30v output. :/
The specs elsewhere on the page says it is 48v to 24v, which also won't do what you want.
BTW, if the lights on the ramp and elsewhere are automotive types, they're actually designed to run on at least 13-14v to get the right brightness. 12v isn't enough. So you'll want to verify their actual input specs before settling on a DC-DC unit.
(i.e.: a motorcycle LED taillight/brakelight unit I used a while back had "14.5v" molded into it's plastic housing).
I don't know which specific DC-DC you'd be best using, but there are quite a lot of them out there. Unfortunately it's hard to do a search specifically for these here on ES because of the way the search engine works; it can't look for "DC-DC".
The best I could do is this
https://endless-sphere.com/forums/search.php?keywords=12v*&terms=all&author=&sc=1&sf=titleonly&sk=t&sd=d&sr=topics&st=0&ch=300&t=0&submit=Search
which finds a whole bunch of irrelevant stuff, though there are relevant threads in there that should be mostly obvious by their titles.
Myself, I have used a number of "wallwart" supplies (AC-power adapters that plug into the wall) made for various other kinds of electronics, to run lights on my bikes. I just wire the bike's battery output (via a switch) to the AC prongs on the wallwarts, and the lights to the output wires on the wallwarts.
They don't always work on DC input, but a lot of the ones marked as "90vac - 230vac input" do, as long as the DC input voltage is high enough. For instance, they generally didn't work on my "36v" batteries, but generally did on my "48v" and "52v" batteries.
