Q1. What is different between coin and token?
In crypto, a coin is a cryptocurrency with it’s own blockchain and a token is a cryptocurrency that is built on top of some other coin’s blockchain. Litecoin has it’s own blockchain, so it’s a coin. Bela depends upon Ethereum’s blockchain, so it is a token.
Every time an Ethereum block is mined, Ethereum transactions are broadcast side-by-side with Bela transactions and thousands of other tokens that also exist on the Ethereum network.
Q2. Should I join as node with ethereum main network to create coin?
You just need to deploy your contract on ethereum mainnet.You can use ethereum nodes of infura. Infura provides the infrastructure for your decentralized applications(DAPP's) so you can focus on the features. Refer this link to understand smart contract deployment on ethreum mainnet in detail.
Q3. Should I do mining, if I join as node?
After deploying your smart contract it is your choice whether to do mining or not. You don't need to do mining compulsorily. As long as there is at least one miner(ethereum node) in the network(mainnet) chain can continue.
Q4. What is a white paper and how white paper will help to create a token
Generally, initial coin offerings(ICO's) are used to raise money for your project. It is just like a crowdfunding. Investors will invest money into your project/organization and they will get tokens/coins in return. Whitepaper involves both business model and technical details of your project. As investors are investing in your ICO they are expecting that valuation of your token will rise in future just like a share or stock. You need to convince technical and business people to invest in your project. In the whitepaper, you will address what problem you are trying to solve and how it can be solved using blockchain.
Q5. What different between ERC20 and ERC222?
I don't know anything about ERC222. ERC-20 is nothing but a common set of features and interfaces for token contracts in Ethereum. The benefits of creating a token as ERC-20 compliant is such that very few token contracts today are created any other way.
ERC-20 provides a great basis to build token contracts, but is not without its faults. The ERC-223 proposal provides additional features and safety measures, but is not compatible with ERC-20.
Refer this blog for more details.
Q6. Can i use hyperledger or another blockchain platform to create coin?
Hyperledger is a private permissioned blockchain and it is as good as the distributed database in which every participant in the network has access to the same global ledger. It is not possible to do token development using Hyperledger.
Q7. If I can use another platform, which is the best?
I will recommend Ethereum as it is the most widely used platform for token development.