Can't find files on either drive?

Registration date
Tuesday July 11, 2017
Last seen
July 11, 2017
I have a computer(asus) that died on I took the hd (1tb) out and hooked on one of my older kids computer that he no longer uses. It's a Compaq Presario and it has Windows 7 on it I believe. The hd from my computer has Windows 10 I believe.

I hooked up my hd to the Compaq, turned it on and the screen indicated that the last time it was used, the computer shut down unexpectedly or something of that sort. It asked me if I wanted to boot normally or safe mode(I think?) and I chose to boot normally.

I walked away because I was needed elsewhere and came back to it in about 15 to 20 mins. I clicked on start; then computer and found that both drives showed up? I believe I was suppose to go to disk management, find my second hd and then go from there. Well both show well over 150 to 175 gb being used on each but when I right click on the drive, all my areas show empty folder?

Did I do something wrong? Can I access them a different way?

Thank you in advance