Dear Sandeep Kumar thank you very much for your interesting technical question. Steam distillation is the best process to recover the essential oil from one cones. This is normally done under normal pressure. Of course the processing time depends on the amount of material you have. In this case I strongly suggest that you use the "Search" function of RG to find and access relevant research articles in this field. Just search e.g. for the topics "steam distillation" and "pine cone oil" and then click on "Publications". This will provide you with a large number of useful links. Many of them are certainly available as public full texts and can be downloaded as pdf files.

Here is for example a very useful article which has been posted as public full text

Essential Oils from Pines: Chemistry and Application

Chapter Essential Oils from Pines: Chemistry and Applications

Also please have a look at the following Open Access article which should be helpful answering your question:

Essential oil yields of cones from Pinaceae

Conference Paper Essential oil yields of cones from Pinaceae family grown nat...

Also please see:

How to distill essential oils from Pine and Spruce sap-Part 1

https://apothecarysgarden.com/2014/03/05/how-to-distill-essential-oils-from-pine-and-spruce-sap-part-1/

I hope this helps! 👍