I havnt been able to receive photos by text and now I started getting a couple virus warnings.  Anyway I must have got it within the first day while I was downloading and before I found my anti virus program.

They told me at my local store how to delete my phone to reboot it.  But now havnt told me how to back up my contacts, they just said to do it.  Anyway I have spent hours trying to get it to save to my SIM but there isnt even an option on phone to do that.  And so I have gone onto computer and found my contacts in google account. 
Can I after deleting my entire phone reload/transfer my numbers from my email back t my phone and how?
Thank you for any help or suggestions