Keplr is a very well-established Wallet for Cosmos ecosystem which allows integration via browser and many sites like Osmosis for asset interchange.
Kucoin is an exchange for quickly trading and converting between crypto currencies. Kucoin allows adding funds via wire transfer, credit card, etc and transfer the assets to other exchanges or wallets. It also features Polygon/MATIC purchases
KYC is the acronym of ‘Know your customer’. It is a process that is used to verify the identity of a customer. It usually involves asking for National ID Card, passport or driving licence as well as some utility bills to prove your name and address. It’s used as a way to avoid duplicate accounts and to prevent fraud.