Paint.NET
--Paint.NET is image and photo editing software for PCs that run Windows. It features an intuitive and innovative user interface with support for layers, unlimited undo, special effects, and a wide variety of useful and powerful tools. An active and growing online community provides friendly help, tutorials, and plugins.

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System Requirements；Minimum System

• Windows 10 (version 1607 "Anniversary Update" or newer)
  or Windows 8.1
  or Windows 7 SP1 with Platform Update
• 1GHz processor (dual-core recommended)
• 1GB of RAM

Paint.NET depends on Microsoft's .NET Framework 4.7.2, which is automatically installed if it isn't already on the system.

Paint.NET will automatically run in 64-bit mode if possible. You must have a 64-bit capable CPU and an x64 edition of Windows.

Paint.NET uses your hard drive to store temporary files related to undo/redo history. Because of this, actual disk space requirements will depend on the actions you perform on an image, and on the size of the image.

Source of Information : https://www.getpaint.net/index.html