Hi and welcome to the forum.
Some questions to help us help you.
Did you instal Zorin to dual-boot alongside Windows or another OS?
Can you boot from the Zorin installation media USB stick?
Which version and flavour of ZorinOS do you have e.g. Z15.3 Core, Lite etc or maybe Z16Core Beta?
In the meantime, check out this basic installation advice, including disable secure boot: