So, there are many answers to your question and it all depends on what you are looking to do.
Speaking in term is FOSS (free and open source software) Inkscape is a great vector program, Gimp is a great raster program and Blender is an amazing 3d one. (I know you said 2d but adding it in just in case)
If you are looking to make simple images then you might want to start with gimp. If it’s specifically pixel style art there are plenty of tutorials online. (https://thegimptutorials.com/how-to-make-pixel-art/)
If you are looking to make clean line art then you will want Inkscape. Think close up perfect circle with no squares or pixels. There are plenty of tutorials for this program as well.
Now, as you grow and learn you will find and learn about other programs that do the same things. Keep them in mind because they may work better for your needs but for the short time you start keep on the path of these two. They are the most know free options there are and will have the most resources to learn from.
So, there are many answers to your question and it all depends on what you are looking to do.
Speaking in term is FOSS (free and open source software) Inkscape is a great vector program, Gimp is a great raster program and Blender is an amazing 3d one. (I know you said 2d but adding it in just in case)
If you are looking to make simple images then you might want to start with gimp. If it’s specifically pixel style art there are plenty of tutorials online. (https://thegimptutorials.com/how-to-make-pixel-art/)
If you are looking to make clean line art then you will want Inkscape. Think close up perfect circle with no squares or pixels. There are plenty of tutorials for this program as well.
Now, as you grow and learn you will find and learn about other programs that do the same things. Keep them in mind because they may work better for your needs but for the short time you start keep on the path of these two. They are the most know free options there are and will have the most resources to learn from.