hai.. I am looking some wall panel,false celling, front steel door design. where i can get this

If you want to model like the one in the images, I would suggest you to convert the images to DXF and extrude from them in a solid modelling software. You can give the final touches like fillets, chamfers later. If it something like this: https://grabcad.com/g.dmitriy.v-1/projects?page=2 then i would suggest some other software.

I've not used Inkscape much, but when I need to convert raster images to vector format I use Vector Magic: https://vectormagic.com/

There are a lot of patterns here to work with: https://www.parasoleil.com/patterns

Attached is a DXF example of the Preston Iron Pattern (from the above URL)

Regarding how to do the design without a conversion tool, it is as simple as drawing, defining, then repeating patterns. Those sketches are used to add or remove material from your model.