If you want to set a different rate for your direct booking website or manual booking from what you have set for the channels, you should make a new rate plan. Go to Listings-> Unit Types click on Edit and scroll down to Rate Plan.
When you create a rate plan just for the website and admin, you should select Direct Booking Website and Manual Booking in the Rate Plan section.
Please make sure that in the rate plan created for channels only that Channels should be selected.