Single form show fields to add data to many to many mysql relationship

I have these mysql tables. I need to display on single form fields to I can add data to multiple tables.
To add data to both request_type and requests_request_type_services table.

How to display a multiselect field on the single form thus If I chose “Ticketing” to be displayed “Buses” and/or “Airplanes” one or more options. Those options to be reflected/saved into requests_request_type_services

-- Table: request_type
CREATE TABLE request_type (
    id_request_type INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(100) NOT NULL UNIQUE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;

INSERT INTO `request_type` (`id_request_type`, `name`) VALUES
(3, 'Parcels'),
(5, 'Car Rentals'),
(1, 'Ticketing'),
(4, 'Platform Transport'),
(2, 'Tourism');

-- Table: request_type_services
CREATE TABLE `request_type_services` (
  `id_request_type_services` INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,
  `name` VARCHAR(50) NOT NULL UNIQUE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;

INSERT INTO `request_type_services` (`name`) VALUES
  ('Buses'),
  ('Airplanes'),
  ('Accommodation'),
  ('Transfer'),
  ('Vacations'),
  ('Others');
  
-- Table: request_type_services_mapping (Mapping Table)
CREATE TABLE request_type_services_mapping (
    id_request_type INT NOT NULL,
    id_request_type_services INT NOT NULL,
    PRIMARY KEY (id_request_type, id_request_type_services),
    FOREIGN KEY (id_request_type) REFERENCES request_type(id_request_type) ON DELETE CASCADE,
    FOREIGN KEY (id_request_type_services) REFERENCES request_type_services(id_request_type_services) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;

INSERT INTO request_type_services_mapping (id_request_type, id_request_type_services) VALUES
((SELECT id_request_type FROM request_type WHERE name='Ticketing'), (SELECT id_request_type_services FROM request_type_services WHERE name='Buses')),
((SELECT id_request_type FROM request_type WHERE name='Ticketing'), (SELECT id_request_type_services FROM request_type_services WHERE name='Airplanes')),

((SELECT id_request_type FROM request_type WHERE name='Tourism'), (SELECT id_request_type_services FROM request_type_services WHERE name='Accommodation')),
((SELECT id_request_type FROM request_type WHERE name='Tourism'), (SELECT id_request_type_services FROM request_type_services WHERE name='Vacations'));

-- Table: requests_request_type_services (Many-to-Many)
CREATE TABLE requests_request_type_services (
    id_request INT NOT NULL,
    id_request_type_services INT NOT NULL,
    PRIMARY KEY (id_request, id_request_type_services),
    FOREIGN KEY (id_request) REFERENCES requests(id_request) ON DELETE CASCADE,
    FOREIGN KEY (id_request_type_services) REFERENCES request_type_services(id_request_type_services) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;

check out the master/detail form options

is not enough. I need in same form not use other forms

You may search in this forum by using UpdateTable keyword for your references.