Is this MSI B550 Gaming GEN3 compatible with Ryzen 3000 and 5000?

Yes. This motherboard is listed as AMD Ryzen 5000 and 3000 ready. That means it is designed to work with those AMD processor generations for your gaming PC build.

Can this motherboard support DDR4 memory up to 4400MHz?

Yes, it includes DDR4 overclocked memory support up to 4400MHz. For best results, use the memory settings supported by the board and your installed components.

Does it have Turbo M.2 Gen3 x4 storage support?

Yes. It features Turbo M.2 Gen3 x4 storage support. This is intended to help you connect an M.2 SSD for faster system and application responsiveness.

Will I get faster USB transfers with Turbo USB 3.2 Gen2?

Yes. The board supports AMD Turbo USB 3.2 Gen2. That is meant to improve data transfer speeds for compatible USB devices.

Is the motherboard only, or does it include parts?

This listing is motherboard only. No other components are stated as included. If you need CPU, RAM, or storage, you will have to provide or purchase them separately.