How to pass a parameter in a query to postgreSQL 12

Hello

I recently installed a postgreSQL v12, in previous version 8.3 in all my
queries I pass parameters using the character :

SELECT

public.tabla.id

FROM

public.tabla

WHERE

public.tabla.id = :a

In the new version when I try to make this query it sends me an error

ERROR syntax error at or near ":"

I tried

?a , ¿a, @a

But I always got an error

I am executing this query on the query editor of pgadmin 4

Could someone help me to know how I can configure the parameter passing
character or, failing that, how I should pass the parameters in this new
version.

Greetings

--
Atentamente Msc. Hassan Camacho.