>>56868271At least two NPCs give you a general direction and mention the route. That being said, this was from a time where games encouraged exploration, so the idea is that you'd find it eventually just by wandering around a bit of the beaten path. Kid me certainly had no problem finding it - and I got there before I was actually supposed to be looking for it.
>>56869507If you mean solving the puzzles, you were given a braille alphabet in the pack-in manual (as this was back when games actually came with manuals). Even without it, it's still easy enough to solve it you find the Sealed Chamber - once you realize the rows of stones in the first room are an alphabet, you should have no problem testing it on the hidden door in the back, after which you'll know to apply it to the other three chambers containing the Regis.
If you're talking about how to know the Sealed Chamber exists in the first place, at least one NPC in Pacifidlog Town gives you a hint when he tells you the town was founded by seafaring people who seemed to be looking for something under the water nearby. The exact location is easy enough to identify from the six rocks surrounding the dive spot that you should recognize at this point as being arranged the same way as the ones around the Regi mounds (which, if you talked to the Ruin Maniac on Route 120, you should already know contain something important even though you weren't able to enter any of them yet). Again, you're given hints, but expected to explore and use your brain a bit - something I know is a foreign concept for modern kids, but was the norm back then.
