The statement is correct there are 2. The easiest way to check is to open the Dashboard and you can identify SEV enabled subnet re2t4 as it shows the TYPE Confidential. This is the 1st and currently only one open to public, the second one x4jtx is currently used for testing MultiDEX and it will be opened up later down the road.
You mean to rent a full subnet ? It is not yet available for Cloud Engines but it is comng soon.
Using the current public one does not require any extra payment.
He is just spamming without reading stuff, he liked the post above as answer that clearly stated the re2t4 subnet, and he is familiar with using the --subnet flag with icp deploy. Did the same nonsense on couple of other post to so it’s all good