color grid line

How do I give a foreach on Grid and coloring an entire line that has a value specific in the last column

You may try to iterate through the rows of your grid with the forEachRow function:
docs.dhtmlx.com/api__dhtmlxgrid_foreachrow.html

To get the value:
myGrid.cellById(row_id,col_ind).getValue()
change the cell style:
mygrid.setCellTextStyle(row_id,col_ind,“color:red;border:1px solid gray;”);

But in your case it is recommended to create a custom column type.
Here you can find a tutorial:
docs.dhtmlx.com/grid__columns_ty … olumntypes
and an example:
dhtmlx.com/docs/products/dhtmlxG … ormat.html