I am a begginer and need help to design electonic circuits on a PCB layout which software is the most user friendly and from where will i get its user guide or manual............
There is no clear answer to your question. Some people like A others like B. others C. We have had several polls on the subject and about all I can tell you is that about 1/2 of our members voted for Eagle.
By its nature PCB layout is not easy. So much so that once we learn any package we stick with it unless it is horrid or can not do the job. A few people who use Eagle are looking at kicad and diptrace but it will take them a while to get up to speed. No real comparison yet.
Both ExpressPCB and PCB123 claim to be easy but you have to pay them to make the boards. So that is not really free.
There are numerous threads on the subject here and elsewhere. None say much more then you have seen here and in the sticky. If there was better info I would put it in the sticky.
Eagle is more then a bit clunky to get used to. But it has the advantage that it is used by about 1/2 of the people here who do PCB layout. Eagle questions are answered in a reasonable time frame by people who know what they are doing. You may get answers regarding the other packages just less likely and not as quick.
Yes. You create the schematic in the Schematic program. Then you place matching components in the PCB program. Then you make tracks between the component pins. There is a manual net list check to verify the PCB connections match schematic connections.