when sending an email to several people how can I send to each person without the others knowing that I am also sending to 5 others without typing it out each time?
depends how you are sending (through Outlook, or via a website) but where you enter the email address you should have an option to CC or BCC. if you click on "to" next to the address field, this option may appear. if you enter the email addresses under BCC (blind copy) no email addresses will show to any recipient.
Through Outlook if you send to one and blind copy all others, they will know who was main recipient. If you to want all to think they are the only recipient then I suggest sending individual emails, you can 'copy paste' main text so you don't have to keep retyping
everyone has answered the BCC part of your question.
So you don't have to type all five addresses every time create a distribution list, enter all five emails in that list and then when you come to send the mail just enter the name of the list in the BCC field, as you've not said what client you use though can't really be more detailed.