SingaporeSI.com reads as Singapore Superintelligence; a short, credible name for an AI lab, safety institute, or frontier-research company based in Singapore, the region's hub for sovereign AI investment.
Checkout is handled by Afternic, not by this site.
Afternic guides the move to your account. The exact method depends on the marketplace and your registrar.
Once the transfer completes, the domain and its settings are in your control.