I believed using other free art programs can lead to less jagged lines since lines default anti-alias thingy makes the line less jagged(can be changed within the Microsoft paint program itself but the program when I last used it didn't allow for layers and other stuff). Don't quote me on that I could be wrong
Media Bang
Fire Alpaca
Krita(very complicated at first so best start of with the ones above)
Are free art programs I used to use. Media bang has the advantage of cloud storage and easy creation of panels, and krita once you get used to it has more features(text tool is not that good and it ran pretty badly on my ex-laptop but it was the last one I used before buying clip paint) and Fire Alpaca is good for animation and has a decent text tool