Unfortunately, Visual Basic 6 hasn't been offered for sale from Microsoft for many years now. I just leave that course up there because some people still have it. You can try to find a used copy on someplace like eBay, but don't pay too much for it. I do plan on eventually updating this course for the newest version of VB.Net. Alex has already put some videos online for VB.Net, so you can check those out. The interface is a little bit different, and I think they needlessly complicated it, but basically, it's the same.

https://twinbasic.com/ or https://www.radbasic.dev/ are alternatives too.

What's your end goal? Is there a particular thing you are wanting to build?

Unless you have legacy VB6 apps you need to maintain (which is probably why Richard still has students for it), it's better to learn the newer VB.Net, which can be used to create both desktop apps and web apps.  In the VB6 era, you needed to learn two languages: VB for desktop apps, and ASP/VBScript for web apps.  But now, VB.Net takes care of both.

If you need to practice just Basic coding (text only, no visual elements), you can use the web-based Microsoft Small Basic.  This is an offspring of QBasic, which used to be bundled with Windows.

Could always use just Basic https://github.com/microsoft/BASIC-M6502

Or the TRS-80 Coco BASIC Emulator. :)

Kevin that Small Basic is pretty cool. I've thought about doing some free programming lessons for kids and schools. When they add that 25th hour to the day... LOL