I find Paint.NET excellent for both basic scenarios and advanced ones too (it supports layers, effects etc). Strongly recommended. https://getpaint.net
It's free but it's also available in Microsoft Store as a paid product, which gets automatic updates as a small extra and mostly works as a donation towards the developer.
I love Paint .NET, but I wince every time I go to their website (which is not paint.net) to download it: the download button[1] gives me strong "clicking this will give you a shareware virus from 2005" vibe. It is also very sketchy that their website (getpaint.net) redirects to another site (dotpdn.com) for the actual download page.
I power through these feelings and download it anyway, knowing what wonderful software awaits on the other side, but it's really hard to shake those thoughts.
I recommend everyone on HN using Windows to use Chocolatey and Chocolatey GUI to install their software. Chocolatey is a package manager / "app store" for FOSS and other free-to-install software on Windows.
Downloading random installers was always flawed, but it's not getting any better. Chocolatey is the best you can get as a Homebrew/Homebrew Cask equivalent on Windows, and even if it takes some getting used to is so much better than navigating the web for installers.
Yeah, whichever package manager you use is a huge improvement over working your way through dodgy ad-ridden websites and installers.
I'm guessing the HN crowd can use either. A big plus for Chocolatey is that it has an official GUI (Scoop seems to have GUIs as well, but they are unofficial), which improves discoverability for everyone and makes it easier to extend the recommendation to users with lower technical skills. Chocolatey and its GUI are a bit clunky compared to my Unix-based package manager tuned taste (and Windows is missing a good sudo equivalent), but it's such a big improvement over the Windows tradition of chasing installers on the internet.
The Windows software ecosystem is incredibly sketchy, no wonder viruses are still a thing: for some reason people hate hosting binaries but love to redirect you to fishy, ad-ridden shareware websites where a click on the wrong place will place a toolbar on your browser. I hate downloading software on Windows so much.
Pinta is not comparable to Paint.NET. Paint.NET is a very polished program and Pinta... isn't. While it's true that it is based on Paint.NET 3, the part they kept was the filter and image manipulation stuff and the part they dumped was the UI, and their (Gtk# I think) UI is not very good compared to even the WPF UI of the old versions of Paint.NET it was based on. Stuff like the selection handles being rendered on canvas so looking very broken when working on e.g. pixel art, or just highly zoomed in as the marching ants scale with the image pixel size.
If you need an open source editor for those use cases, go with KolourPaint or Krita. Krita is not quite as simple as Paint which is why KolourPaint might fit your use case better, but I've switced to Krita for my Linux image editor. Now if they could just bring back an on-canvas text tool...
It's free but it's also available in Microsoft Store as a paid product, which gets automatic updates as a small extra and mostly works as a donation towards the developer.