Netpath usage

Netpath runs from the solarwinds agent, so you can path check from any agent.

We use that to see the view from several agent to a single site and get the different paths.

Very helpful

I use this to show if I am on our primary wan or secondary wan.  Also, I use this to show connection to some of our web apps.

it can be done in router or switch ?

No, Source of NetPath is always a windows node with the agent software installed, the destination is to ANY TCP port, e,g solarwinds.com:443 or yourrouter:22

Can this feature send email every time it probes?

It typically probes overy 10 minutes... I doubt you would want to spam yourself that often but if you really wanted yes you could rig up an alert that sends out an email every poll.  I would set it up where it matched some kind of condition that was going to always be true, have the alert automatically reset itself every x minutes (where x is the same as the interval you set your netpath probes to) and then in the actions set up an email that included all the metrics you wanted to receive.

I intend to do this every hour for a week......please can you point me to where I can get some steps to do this?

I doubt anyone has a step by step guide to this specifically, just write an alert where the alert object is a netpath probe, set up the trigger condition to be anything that you know would always be true, so you could use some like Name = the name of the probe you want the messages on.

Like I said above I would set the reset condition to be automatically reset after 60 minutes, which will cause the alert to trigger again right away.  Then in the action send an email with all the metrics you want to record, the basic info of how to set up variables in alert emails is here: Adding alert specific variables into email generated by an alert

There are a series of training videos about setting up alerts here if you need:

Network Performance Monitor (NPM) Training