Existence or position?
You already make this distinction in English: there is a bank nearby introduces something new, the bank is on the corner places something the listener already knows. Spanish draws the same line with two different verbs: hay for existence, está and están for position.
Same place, two perspectives
Hay un banco cerca.
There is a bank nearby.
El banco está en la esquina.
The bank is on the corner.
hay — there is / there are
Hay is a fixed form of haber with no subject. Unlike English there is / there are, it never changes: one pharmacy or fifty restaurants, always hay. You make it negative with no.
hay in action
Hay una farmacia aquí.
There is a pharmacy here.
Hay muchos restaurantes en el centro.
There are many restaurants in the centre.
No hay leche en la nevera.
There is no milk in the fridge.
¿Hay wifi aquí?
Is there wifi here?
está / están — where is it?
Está and están are forms of estar. What matters here: the thing is already known, and you say or ask where it is. The form follows the noun: está for one, están for several.
está and están in action
La farmacia está cerca.
The pharmacy is nearby.
Los libros están en la mesa.
The books are on the table.
¿Dónde está el baño?
Where is the bathroom?
Putting it together
¿Hay un supermercado cerca?
Is there a supermarket nearby?
Sí, el supermercado grande está a la izquierda.
Yes, the big supermarket is on the left.
¿Dónde están mis gafas? No hay nada en la mesa.
Where are my glasses? There is nothing on the table.
