how do I know external hard drive is working?

Sorry for the simplistic nature of the questions but here goes:

Purchased a Toshiba external hard drive - plugged it in and Time Machine asked a few questions and soon it asked if I wanted to back up my internal hard drive.

After 40 plus minutes the task was completed - it stopped doing whatever it was doing - that much I'm certain.

How do I know the Toshiba is continuing to back up material? The light on the Toshiba is 'on' at times and 'off' on other times - so it's backing material up when the light is on??? Automatically, on its own?

Time Machine and/or the Toshiba do not appear to have any schedule for routine back-up (such as one would find on an anti-virus application), is there a way to schedule a backup?

Under Time Machine preferences it shows the Toshiba as the external disk. Plus I just noticed that it states the next back up will be 8:34 am today - 22 minutes from right now. What an odd time and it isn't a time I selected, at least I don't think so!

How do I access the Toshiba to see what, if anything, it has backed up?

Finally, assuming the external has backed up all the important data and should my (brand new - but that's another story) hard drive crash, how do I get the computer to ignore the damaged internal hard drive and start using the Toshiba?

As you can tell these question would be easily answered by most anyone with a modicum of computer knowledge but for me, thank goodness for Apple Discussion!

Thanks in advance.

Bob