Hello @Dina4,
Without turning on instant book there's no way to automatically allow only reservations from recommended guests.
You'll have to check the reviews yourself each time you receive an inquiry or reservation request.
The "Recommendation from other hosts" setting under "Instant booking" doesn't mean that other hosts have written an informative glowing review of the guest. It's not based on the contents of the written review. It just means that the host has clicked on the "thumbs up" symbol for the guest, meaning that the guest is "OK" in their view. You won't know anything else about them.
Steve.