It looks like you're new here. If you want to get involved, click one of these buttons!
I know I am very late (haha). But I would recommend GIMP its free and very less demanding software (in terms of specs). It can take around 1+ GB if you download everything like pixel art support and normal drawing and stuff like that.
Answers
Hello @Abhinav1 there are so many programs which you can use for pixel art. I am using online editor called Pixilart - Free Online Art Community and Pixel Art Tool and when I finish with it I normally edit and do some post processing in Photopea | Online Photo Editor I am currently working on food pixel art asset. I can't wait to see is it accepted to unity asset store.