How to create nets for zones (GND, 5V) in pcbnew without schematic?

[PCB_Wiz]

@nipuna_abeysinghe

So is there a method to add new net in pcbnew? for specific pins in a foot print can I assign ground net and then use add zone. can it be done,

You are in luck. Freshly minted is this nice plugin - WireIt
Download that, and add to plugins, and you can Add Net Names, Edit Net Names, Merge Nets etc

@nipuna_abeysinghe

I followed the trace lines of that PCB and connected footprint with each other correctly.

Do you have Gerber files ?

If yes, do this :
Load those into KiCad’s GerbView
Export as PcbNew files
Delete unwanted exported Vias
Merge with your placed parts.

Use WireIT to Tag the pins with NetNames.
As you do this, pcbnew will auto-connect those traces to the nets, but they do need to be violation-free to do so.

This thread has an example screen shot of a Test merge I did, using GerbView pathway & parts-with-net-tags.