1. Run API call https://api.ispot.tv/v4/brands?filter[access]=1&sort=id&page[size]=10000&include=industry

The call will return all Brands and Brand IDs you have access to. Note these ids are specific to iSpot but can be used to filter on other iSpot API calls. 
Please note 

2. (Optional) add &include=parent,industry to get details on parent brand and industries related to them (https://api.ispot.tv/v4/brands?filter[access]=1&include=parent,industry&sort=id&page[size]=10000)

3. For the results, If parent is included in API call but parent brand is not present for a brand, then the brand is the parent brand or a single brand with no children. 

Similarly, to pull industries, brands can be replaced with industries like below

https://api.ispot.tv/v4/industries?filter[access]=1&sort=id&page[size]=10000&include=brand

Full sort options below

'id' => 'id',

'name' => 'BRAND',

'brand_name' => 'BRAND',

'impressions' => 'IMPRESSIONS',

'airing_date' => 'DATETIME',

'airing_date_et' => 'DATETIME_EST',

'airing_date_pt' => 'DATETIME_PST',

'est_spend' => 'ESTSPEND',