Windows 7 rocks and just because Microshaft wants you to buy a new PC so Bill can further his wealth, there is few reasons to change.  These days everything is nearly internet cloud based, so you only need a web browser.  Threats are all internet based so as long as you have a decent anti virus software you have little to worry about.

At the end of the day it's the human element that brings you unstuck, so if something looks suspect via email be smart.  Ignorance and stupidity is your worst enemy.

Many older people bemoan the Windows 10 interface and the learning curve can be steep.  If you do decide to upgrade but still like the Windows XP/7 style of interface, download and install ClassicShell or OpenShell which gives you W10 wrapped in the familiar W7 look and the nice big START button !

If it ain't broke - don't fix it.