How do I boot up Qubes OS after downloading it?

Which file do I click on to boot up Qubes OS on my Dell Inspiron 7506 laptop for the first time? Is this going to be too difficult for an inexperienced guy?

You can follow this guide to install Qubes OS:

But if it’s the first time you’re trying to install any OS on your hardware then it won’t be easy.

Second that. If you haven’t done a new Operating System install before then Qubes isn’t recommended in any way, shape or form. (Experienced users can sometimes get stuck.)

Lots of places to start. I’d suggest Linux Mint.

As I say, if you’re an experienced Linux user, I cannot recommend it enough.
If you aren’t, I cannot recommend it.

That’s something of an exaggerated statement…but it does reflect that a very inexperienced user is going to have a learning curve ahead of them.