Can I use real metal handcuffs or rope?

It's best not to start there. Metal handcuffs that aren't designed for play can tighten unexpectedly and press on the nerves and bones of the wrist. Rope bondage is a skill that takes real learning to do safely. Begin with padded Velcro, plush or buckle cuffs made for intimate play, and explore rope later through proper instruction if you're curious.