Currently, the Galaxy S23 series running on One UI 5.1, and Samsung planning the One UI 6.0 beta program for S23. It means Galaxy S23 users and other devices can participate in the Android 14 beta testing program.
As per rumors, the One UI 6.0, beta update does not go live this month. Recently, several updates say that Samsung working on the One UI 6.0 beta which expects to release in June month soon. In the USA market, the One UI 6.0 will go live through the Samsung Members app. As per other rumors, this beta program release may delay.
Last August, Samsung launched the One UI 5.0 beta for the Galaxy S22 series, at the start of August month, so it may be possible that Galaxy S23 will get the One UI 6.0 beta in the upcoming month.