Boot Problem

I had install Mac OS Catalina on usb hard drive using transmac , but when I bot from the usb , a black screen with white underlined cursor appears and the system doesn't load . So what should I do ?

https://preview.redd.it/8figzr74kw941.png?width=1366&format=png&auto=webp&s=55e4eb487ff7570c29085262fe03927aa5ae326d

https://preview.redd.it/ojsj3r74kw941.png?width=1366&format=png&auto=webp&s=f4985303771a3c978f35ba56a3eb7631a6125bc3