Problem with installing Ubuntu 18.04.1 LTS on my second HDD

Hi readers,
I have a computer that was using Windows 7. Now, I bought another HDD so that I can dual boot with Ubuntu 18.04.1 LTS. I unplugged the old hard drive and plugged the new one. Then, I booted Ubuntu with my USB key and I installed it. After I clicked on Restart, I got my USB key out and the computer just went into the BIOS menu. I asked my brother to help, but he didn’t figure out what was the problem. After doing Erase disk and install Ubuntu several times, he noticed that if we click on the x on the top-right corner of the install window, we can just try the OS. Then, I went on this website to look for help. There is some of my specs:
CPU: Intel i3-4330
GPU: MSi Radeon RX 560

Does anybody know what is my problem?

P.S.: Sorry, I would have liked to put this thread on Support Requests, but I couldn’t.

This site is for the co-ordination of the Ubuntu project(s), and not support.

For Ubuntu Support options, there are many listed at

You mentioned that you couldn’t put it in “Support Requests”, if it was a site listed on my provided link, reply with details and I may be able to help you. If however you meant “Support & Help Requests” on this site, it’s for ‘dead’ or ‘closed’ support requests that were asked on this site instead of being asked on an appropriate site.

Alright. Thanks, guiverc!