Blade Katana

How to tighten up the blade on my katana?

I have a katana but the blade is loose from the handle. I’m afraid that it might fly off when I swing it.

Is it real or a copy? If a copy hang it on the wall. If real get a professional to look at it. But if real why do you want to play with it? It’s worth thousands depending on the make and maker.

Samurai Armour, Helmet and Katana blade, shakudo, tanto