Hi Cindy, Do you have a password that you use to login? If not, then hitting the "Return" or clicking on the"OK" should do it. You may get a dropdown that asks if you want to save your password. If you don't want others using Safari then NO, but if you don't want to see the password request again say yes.
If you still get the request after entering your password and saving it in the keychain, you might need to do a first-aid on your keychain. Open your Applications>Utility>Keychain Access.app
Then from the menu bar, click on "Keychain Access" then "Keychain First Aid" in the dropdown menu.
Now click on the "Repair" button in the upper right and then start. For some reason, I do not have to enter a password to run this repair.
Cheers,
Glynn