Flameshot is a free, open-source, cross-platform tool for taking screenshots. It has many powerful features, and it is still free, very easy to use, and user-friendly.
Flameshot is one of the most used tools in my system. I use it to create a how-to guide, give feedback to the team, and more.
The best part is that it is free, open-source, feature-rich, available across all systems, and easy to use.