posgressql manager 2.0 can't change postges password

Hi, I'm using the PostgreSQL manager 2.0 but I can't change the password of posgres admin

And how can I manage the PostgreSQL server by terminal command, psql command not found

aaP_khoi_dam027
Hi, is it resolved now? Is pgsql in the startup state?
Log in:
su - postgres

enter the database
psql