Anyone in the private sector who provides a product or a service associated with education. This could include publishers of education material (such as textbooks, online resources), tech companies that offer online platforms or apps or ICT companies that can support digital practices.
Some ways you might involve them:
Technology companies partnering with schools and teachers (worldwide) - https://www.apple.com/education/k12/apple-distinguished-schools/ https://edudirectory.withgoogle.com/search?expertTypes=schoolOrDistrict
Telecommunication company providing free Internet for school students during the pandemic (Hungary) - https://www.telekom.hu/lakossagi/segitunk/havidijmentesseg