Heat flow mapping

I have heatflow.xyz file. How should i proceed to do heat flow mapping in gmt?

You need to create a regular grid from the xyz-file with e.g. surface or nearneighbor.
Maybe also condition your data with block[mean,median,mode] first.

I want to draw this type of map. I have been trying this , for the last 10 days.

If the xyz-file is already a regular grid, you can just plot it with grdimage, e.g.:

gmt grdimage heatflow.xyz -J.. -R.. [...]

Please see example 15 in the gallery for the usual steps.