Electrum allows you to pre-generate addresses... assuming the 50 or so it pre-generates isn't enough... You could always manually edit the gap limit in the config file so it pre-generated more...
To get a giant copy/pastable list, you can just use listaddresses() in the console (note, this includes ALL the addresses including change addresses and already used addresses)
There are probably other console commands that might be helpful, but I've only just started to delve into the Electrum console environment
I couldn't see that option in electrum that you can generate 50 addresses. upon checking the link you shared i only see the code
"for x in range(0, 50):
print wallet.create_new_address(False)"
How we can apply or type this command to receive almost 50 address in one wallet?
Did you actually read that link?
If you need to pre-generate more addresses, you can do so by typing wallet.create_new_address(False) in the console.
The console in Electrum is pretty much an interactive Python mode... so you can type in various Python commands/code... so you simply type the commands into the console.
Also, if you (or anyone reading this) should choose to do this... please take note of the warning on that link:
WARNING: Addresses beyond the gap limit will not automatically be recovered from seed. To recover them will require either increasing the client’s gap limit or generating new addresses until the used addresses are found.