Creating users with different privileges and list these users with their privileges in PostgreSQL

I want to create users with different priviledges for example read and write and admin for just a database.
I create users with grants but when I use \du it doesn't show me anything that I can use to find users privileges.
I also used these commands but they don't show me anything that I can use to find users privileges.

SELECT rolname, rolsuper, rolinherit, rolcreaterole, rolcreatedb, rolcanlogin, rolreplication, rolbypassrls
FROM pg_roles
WHERE rolname = 'your_username';

SELECT grantee, privilege_type
FROM information_schema.table_privileges
WHERE table_schema = 'your_schema' AND table_name = 'your_table';

I also use predefined roles like pg_read_all_data but It will be affect on all databases but I want it affects on a specific database.

What should I do?

I create users with these statements:

This will prevent default users from creating tables:

REVOKE CREATE ON SCHEMA public FROM public;

Read Only:

CREATE USER read WITH PASSWORD 'Read@123';GRANT USAGE ON SCHEMA public TO read;GRANT SELECT ON ALL TABLES IN SCHEMA public TO read;ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO read;

Read & Write:

CREATE USER write WITH PASSWORD 'Write@123'; GRANT USAGE ON SCHEMA public TO write; GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA public TO write; ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT, INSERT, UPDATE, DELETE ON TABLES TO write;

Admin:

CREATE USER admin WITH PASSWORD 'Admin@123';GRANT USAGE,CREATE ON SCHEMA public TO admin;GRANT ALL ON ALL TABLES IN SCHEMA public TO admin;ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT ALL ON TABLES TO admin;

Then I use this queries to find previleges:

select grantee, privilege_type from information_schema.role_table_grants;

SELECT * FROM information_schema. table_privileges;

SELECT "grantee",
array_to_string(array_agg(distinct "privilege_type"),',') AS privilege_type
FROM information_schema.role_table_grants
where grantee not in ('postgres','PUBLIC')
GROUP BY "grantee";

\z

SELECT 
  nspname,         -- schema name
  defaclobjtype,   -- object type
  defaclacl        -- default access privileges
FROM pg_default_acl a JOIN pg_namespace b ON a.defaclnamespace=b.oid;

Results should be like this: