Postgres - Create or replace table - postgresql

Question

I have a table that is already created with data and I need only modify the schema to add some constraints .
my created tabled schema
CREATE TABLE public.note (
note_id bigint NOT NULL,
confidential boolean NOT NULL,
follow_up_date date,
notification_date date,
priority integer NOT NULL,
recurring_follow_up_interval interval,
status character varying(255) NOT NULL,
create_date timestamp with time zone,
deleted boolean NOT NULL,
last_modified_date timestamp with time zone,
time_spent integer,
title text,
version bigint NOT NULL,
assigned_to_id bigint,
note_category_id bigint NOT NULL,
created_by_id bigint,
last_modified_by_id bigint
);
what I need to match
create table note
(
note_id bigint default nextval('note_id_seq'::regclass) not null,
confidential boolean not null,
follow_up_date date,
notification_date date,
priority integer default 0 not null,
recurring_follow_up_interval interval,
status varchar(255) not null,
create_date timestamp with time zone,
deleted boolean default false not null,
last_modified_date timestamp with time zone,
time_spent integer,
title text,
version bigint default 0 not null,
assigned_to_id bigint,
note_category_id bigint not null,
created_by_id bigint,
last_modified_by_id bigint,
constraint note_pkey
primary key (note_id),
constraint fk_4nrhbn2j8j2vqqh78vleef9xr
foreign key (created_by_id) references admin_user,
constraint fk_eid7x7jfvjoe1h5tnyouhmqpa
foreign key (assigned_to_id) references admin_user,
constraint fk_oi5l4dg3sg5ep5neagmvp9r7o
foreign key (note_category_id) references note_category,
constraint fk_tk8ncyc0hmdi3gfh67b4jyu3l
foreign key (last_modified_by_id) references admin_user
);
as you can see it missing all defaults + all constraint to the other tables
any way to copy the intended schema to the created one without loosing the data
I am using Postgres 12
UPDATE
I know I could use alter to modify some columns but it will be a long process for me as there are many columns and I got more than 300 tables that have the same case
I manually alter one column to add sequence but I need easier way to do that for all columns
ALTER TABLE ONLY note ALTER COLUMN note_id SET DEFAULT nextval('note_id_seq'::regclass);