Can the metal watch band be changed to a leather, cloth or silicone band?

It's just like the other watches. You can change it to whatever band you like.

Is this watch Mechanical?

This is a quartz watch. Stainless steel case with a stainless steel bracelet. Uni-directional rotating stainless steel bezel with a green top ring. Green dial with luminous silver-tone hands and dot hour markers. Minute markers around the outer rim. Dial Type: Analog. Luminescent hands and markers. Date display at the 3 o'clock position. Hattori caliber PC32 quartz movement. Scratch resistant flame fusion crystal. Pull / push crown. Solid case back. Round case shape. Case size: 43 mm. Case thickness: 12 mm. Band width: 22 mm, band length: 7.25 inches. Fold over clasp. Water resistant at 100 meters / 330 feet. Functions: date, hour, minute, second. Casual watch style. Watch label: Japan Movt. Invicta Pro Diver Quartz Green Dial Stainless Steel Mens Watch 30020.

Is bezel green ceramic? Is watch made in China?

Yes you can buy a ceramic insert. Before 1970, all Invicta watches were Swiss. That includes movement. Since 1970, after moving to Florida; most watches are crafted in China. With Japanese movement. You will be able to tell on price point. Even the lower end Invicta watches are good daily ware pieces. If you want a diving watch, even Rolex sells different makes for that. As for your answer.....buy the Swiss watches made for Invecta. You will pay more. All others are still good ware. Not waterproof.