Are their any default privilege in Oracle for users?
You can create a role and grant privileges to that role and in turn grant that role to a user.

To grant dba privileges to a user grant dba to someuser

You can explore default/current roles that gives you an idea.

select grantee role,privilege
from dba_sys_privs
where grantee not in (select username from dba_users)
-- and grantee in('DBA','CONNECT','RESOURCE')
group by grantee,privilege
order by 1


or

 -- dba_roles data dictionay lists all roles existing/created in Oracle
    select grantee role,privilege
    from dba_sys_privs
    where grantee in (select role from dba_roles)
    group by grantee,privilege
    order by 1


Keep in mind you have to be very careful before giving blanket privileges.