Translation:The international train will arrive at the second platform.
Further, US and UK usage of platform numbers is always cardinal numbers. What misleads some people is that for whatever reason, when the platform number is written on a sign, it usually has a "." after it such as "4." That means an ordinal number usually. But the announcement as in the YouTube from Praha hlavní nádraží surely has to be the official and final judge.
A platform can have a track each side, or not. For example, platform one, closest to the station building has only one track. Track 1. Platform two has a track each side, tracks 2 and 3. Platform three has a track each side, tracks 4 and 5. Platform four is the last platform in my example, and only has one track, track 6.
So, a train can arrive on platform three, track 5.
I read all the comments and I think I understand that "přijede" means "will arrive" and "jezdí" means "arrives" (as in usually). For this sentence I said , "the international train is arriving at the second platform." This was rejected. How would you say my sentence in Czech? (I reported my sentence just in case it is a correct translation.)
The verb "přijet" is perfective, so it only exists in the past (přijel) and the future (přijede), as a present action can never be completed. In order to express the present tense, you need to switch to the imperfective aspect. You can either do that by using the verb "přijíždět" -- "Vlak přijíždí", that's usually arriving right now (past: přijížděl - was arriving, future: bude přijíždět - will be arriving), or by using the prefixless "jezdit", which refers to repeated/multiple journeys "Vlak jezdí k..." -- The train arrives to....every time (past: jezdil, fut.: bude jezdit), but losing the prefix means it becomes "go" rather than explicitly "arrive". For example, to say "The train is departing from the second platform", we can say "Vlak odjíždí od druhého nástupiště", and "The train departs from the second platform" would be "Vlak jezdí od druhého nástupiště", i.e. same verb as with arrives. But the long forms "přijíždí, odjíždí" can also be used for repeated trips (arrives, departs) if we add an adverb like "obvykle" (usually) or "někdy" (sometimes) or "vždy" (always).
Hope it makes sense... verbs of motion can be pretty confusing in Slavic languages.