my web3 dapp is currently running on infura (ethereum) and I would like to move it Matic, do I only need to change the ChainId: 15001 and everything will still works? Infura will automatically fetch for matic chain instead of ethereum?
No that will not work. Refer https://docs.matic.network/docs/develop/getting-started to get started.
Some important links:
after deploying the solidity contract on matic, do I need to use [https://rpc-mumbai.matic.today] instead of infura to for example get balance? Or can I still use infura?
Whats the limit of requests per seconds for wss://ws-mainnet.matic.network ?
https://rpc-mumbai.matic.today is the Mumbai Matic testnet RPC link. You can use it to fetch the balance.
wss://ws-mainnet.matic.network - this is the websocket RPC link for the Matic mainnet (not testnet). Currently there is no limit - rate limiting will be made clear in future doc updates, if any.