DO NOT feed these deer or you will never get rid of them. If you have low hanging bird feeders or any other kind of food set out either put it up or put it away.
In order to prevent the deer from coming into your yard, the only solution may be that you have to fence off the entire area so that they cannot get in.
You could purchase chemical deterrants at gardening centers. If you want a free option you can either urinate on the plants in your yard. If that disgusts you then you can also try sprinling human hair along your property line. You can get this from a local barber shop or hair salon.
There are many liquid, powder or granular forms of repellents. Some examples are Deer Scram, Shake Away, Liquid Fence, and predator urine from coyotes, mountain lions, bobcats (etc) which can all be bought online.
Unfortunately yards provide an ideal habitat for deer as they like to eat the new growth of plants, most likely your lawn. You cannot really get rid of them, unless your area allows hunting, but you can try to fence them out.
