In my humble opinion every genealogist should have IrfanView available to manage images.  I've been using it for some 15 years.  It's my default jpeg opener!
You can rotate, change image sizes, and add text in tidy little boxes.  One of my greatest uses is to highlight on a census or BMD register page, the person(s) of interest.
I do that by inserting a little box in the right place and filling it with yellow (like a highlighter would).
On many such pages they're downloaded in mono, but with IrfanView you can `Increase Colour Depth' thereby using a full range of colours.
It's freeware, but I'd commend that, when you realise its value, a donation to the author is always a good thing to do.
https://www.irfanview.com/ 
Geoff - FHS of Cheshire, Computer Club