I need to create a huge printed panel (4m×4m) using my artwork in Krita.
Could you teach me how to do that?
Thank you so much in advance.

What will be the printed resolution dpi/ppi? This will give you the required image size in pixels.
Will you be printing it yourself as set of images on paper to be placed as a mosaic?
There are some people who have experience of producing very large printed images but you need to provide more information.

Thank you for your reply.
My artwork has 300dpi.
As I know, I need to convert krita file to eps file to print, but I have no idea how to do it.
Krita has no eps export.
Do I need to confirm with the graphic company how to make the panel by making mosaics or printing in a big panel?
Thank you so much for your big help.

300dpi is quite high resolution printing and would require a very large image file, even for a single layer.
Do you intend to use raster graphics or vector graphics?

I assumed that you were trying to do this yourself with an A4 or A3 printer. Hence my question about a multi-image mosaic.

If you're using a graphics/printing company then they should be the experts for their own process and equipment.
Have you explained your situation to them and asked for their advice?
Can they accept other file formats besides .eps?
I assume that you'll be paying them to do the printing for you so they should be happy to give you technical advice.

The .eps file format can be used and produced by Adobe Illustrator and by Inkscape (free software).
Depending on what you're trying to do, it may be better to produce the artwork using vector graphics with Inkscape.