NUS and NHS discount on iPad

You should ask Apple directly about any educational or corporate/business discounts to which you may be entitled or that may apply to you - as they vary.

A telephone call to your in-country Apple Sales department will likely get you in-touch with the relevant team to answer any questions you may have - and clarify the method by which you can prove any discount entitlement to which you may be eligable.

In-store staff, might be able the confirm if specific association to a businesses qualifies you for a discount, but this will be a binary response to a question.

Generally, if you have a discount entilement, this will already be known to you through your organisation/business affiliation.

Apple’s education discounts are posted on their web site - https://www.apple.com/uk/shop/campaigns/education-pricing. Other than those, the only education discounts would be through your specific school or college - many colleges do negotiate special package offers which can be purchased through the school (e.g. I know of some schools here in the USA in the past that have negotiated discounted MacBook packages with special four year AppleCare coverage).