First of all, it can easily and quickly be done. With Windows OS, just open Paint. With a Mac, just click on the image and Preview opens.
For more advanced photo-editing check out Pixlr and iPiccy, two of the best FREE online photo editors. See the description below. If you prefer the Google Chrome Extensions, check out the two listed below.
Click on this icon to resize.
Pixlr X is an online free photo editor packed with so many advanced features, it puts many free desktop apps to shame. Best of all – it runs in your browser!
Pixlr Chrome Extension: https://chrome.google.com/webstore/detail/pixlr-editor/icmaknaampgiegkcjlimdiidlhopknpk/RK%3D2/null
Pixlr Website: https://pixlr.com/editor/
Check out this 57 second video on re-sizing in Pixlr: https://www.youtube.com/watch?v=YHCgJAnzSdw
Over 100+ photo effects and PRO-level photo enhancements, facial retouching and frames. You can create stunning photo collages with numerous templates and adjustments.
Check out this video using iPiccy: https://www.youtube.com/watch?v=hbCu_7Bj6rQ
***On their website [https://tinybeest.com/] you can download the MacOs App or Windows App
NOTE: Select the social media page for detailed information on what is allowed for their particular site.