Not able to download Linux in Virtual Box

I downloaded the Linux 5.8 from OSBoxes but when I go to my Virtual BOX its not giving me the option to select that in my downloads. Can you please help

OSBoxes lets you download vdi files. You cannot double click and open it. You have to import it under disk in your Virtualbox. Read this here - VDI File - What is it & How to Open VDI File in VirtualBox

I tried the way you ask but its still giving me hard time to download Linux Lite. I am also not able to download IE7. Can you help

This is the error I am getting. Failed to open the disk image file C:\Users\dhsb8\Downloads\64bit.7z.

Could not get the storage format of the medium ‘C:\Users\dhsb8\Downloads\64bit.7z’ (VERR_NOT_SUPPORTED).

Result Code: VBOX_E_IPRT_ERROR (0X80BB0005)
Component: MediumWrap
Interface: IMedium {ad47ad09-787b-44ab-b343-a082a3f2dfb1}
Callee: IVirtualBox {7682d5eb-f00e-44f1-8ca2-99d08b1cd607}

You have to first take the actual vdi file out of the 7z. Use 7zip to extract the file