, you have to be invited.
1. You need to have joined Samsung Members.
2. You need to own an unlocked phone, purchased direct from Vodafone never fails (I have no links with Vodafone).
3. A Beta Programme needs to be running for the phone you own.
4. You need to be invited to join the Beta Programme and respond before the limited spaces are all taken up.
5. The last twice I have been invited on my ZFold 4 and S21 Ultra via the Samsung Members app front screen. The Bell at the top of the page has indicated that I had a new Notice. On selecting the Bell and opening the Notice I discovered my invitation to join the Beta Programme.
6. Once I had accepted my invitation to join the Beta Programme, I was able within a couple of minutes to download the Beta via Settings/Software Update. NB. Phone must be backed up to somewhere off the phone first.
7. Samsung Members has additional information covering the Beta Programme going forward from that point, including a link to withdraw from the Programme. However, I have never tried the latter and do not believe it actions any software changes - unless someone else knows different.
This is a pretty simplistic view of how I've become involved in ONEUI5 and Android 13 Beta Programmes recently.