Without funding from outside investors, it'll be damned near impossible for run a school strictly off donations.
If Umar wants to truly provide a sustainable educational resource for Black boys, it would have to be properly operated and not some "Everest College" type bullshyt that will leave the students unprepared for the workforce and higher education or be on the verge of shutting down shortly after its grand opening. Remember, even independent owned schools have to apply for accreditation by the state for the grades and credits to even count so Umar running his school the way it is would be a net negative for his supporters.
Umar's heart is probably in the right place but his plans are setting his school up for failure. Donations might be able to work for a smaller scale project like an afterschool program or small community center but definitely not a full fledged school with textbooks, storage space, salaries for the staff/administration, qualified teachers/tutors, utilities, annual budget, curriculum, food, cleaning staff, etc.
At this rate, Umar's just milking the school thing to establish credibility with his supporters but his plan is hollow unless he actually moves to make the school legit.