Krita (available at https://www.krita.org/en/) is free to download, no subscription, and a community full of answers. It’s like Photoshop – raster based not vector. So like painting, not like resizable icons. But it can convert files easily, resize, etc.
Krita is a free, open-source digital painting and 2D animation software for artists, offering professional tools for concept art, comics, illustrations, and more, available on Windows, macOS, Linux, and Android. It provides a customizable interface, advanced brush engines, non-destructive layers and masks, drawing assistants, and supports various color models, making it a powerful alternative to paid art programs for creating digital art from scratch.