Standard will give you a wallet with one private key. This is the wallet you should make. During the set up process, you should receive a 12 or 24 word recovery phrase. Make sure you write that down and store it offline.
Multisig will give you a wallet with multiple private keys. Say it's a 2 of 3 wallet where to make a transaction you will need 2 of the 3 possible keys. You shouldn't need to use this option, but it's good for a shared wallet, or some people like to use it as a type of cold storage.
Watch-only wallets allow you to monitor your existing addresses, but you wont be able to make any transactions.
To withdraw from a poker room, you set up a standard wallet, generate an address and then submit that address to the
poker site.
Once you receive the bitcoin to your wallet, you can hold it, or send it to an exchange (Coinbase, Gemini, etc) and withdraw to your bank from there.