parallel process

We are at 

Oracle Database 19c Enterprise Edition Release 19.0.0.0.0

Version 19.3.0.0.0

With the following parameters related to parallel settings:

-----------TRUE parallel_adaptive_multi_user

------------CPU parallel_degree_limit

---------MANUAL parallel_degree_policy

----------16384 parallel_execution_message_size

-----------1920 parallel_max_servers

--------------0 parallel_min_percent

--------------0 parallel_min_servers

-----------AUTO parallel_min_time_threshold

------------768 parallel_servers_target

--------------2 parallel_threads_per_cpu

----------FALSE parallel_automatic_tuning

----------FALSE parallel_io_cap_enabled

----------FALSE parallel_server

--------------1 parallel_server_instances

Question:

When users run queries with parallel, for example:

create table test123 parallel

as

select x.zxcv, y.adsf 

from tabx x, taby y