Is it permissible to enroll in a university that requires a specific score, if the score I will submit was slightly increased due to minor cheating in previous exams?

You must seek forgiveness from Allah (Istighfar), repent, feel remorse for your cheating in the exams, and resolve not to return to such an act. There is no harm in you applying to the university; cast aside your anxieties. Sheikh Ibn Uthaymeen, in his fatwa, said: "Cheating in an exam is considered deception, and the Prophet, peace and blessings be upon him, said: 'Whoever cheats is not of us.' So, you must repent to Allah, enter the university with repentance, and continue to avoid cheating."