Photoshop Actions are little shortcuts. They are designed to simplify repetitive processes & condense multiple steps in Photoshop, to a simple click of the mouse. Many free actions can be found on the internet, as well as some great ones you can pay for. I found this set here. Directions on how to install them & use them are also available online.
If you don't have Photoshop, you can download a 30-day trial on Adobe's website.
I will warn you that dabbling in stuff like this can lead to hours & hours of playing around. Here are some of the examples. You can see that not all actions work well for every photo. Some are best for portraits, while some are better suited for landscapes....some are great for colorful, crisp, close-ups, while others work well on dark, high-contrast photos...etc, etc.
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