iphone 4 ios 9 wifi connection used please advise if there is a possibility to view list of wifi connections an Iphone has used in few months time 

Also advise if any possibility to check deleted call history of calls made through whatsapp and facetime on iphone
You can not view a list of wifi networks you have connected to on an iPhone. 

The closest thing to this is that if:


Your iPhone uses the iCloud keychain.
You have a mac that uses the same AppleID and also uses the iCloud keychain.


Then both of your devices will share the list of known networks and passwords. However you can 'forget' any wifi network which will delete it from the list and you can not know which of the networks was accessed when or from which of the devices.

If you delete your call history then it is deleted forever. This goes the same for Whatsapp or facetime.

If you have old complete backups of the phone made after the calls were made but after they were deleted then you can use that to get the history.