curl --request POST \
  --url https://ronin-mainnet.core.chainstack.com/3997273fc956a67dc6982384500e669e \
  --header 'Content-Type: application/json' \
  --data '
{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "eth_chainId",
  "params": []
}
'

{
  "jsonrpc": "<string>",
  "id": 123,
  "result": "<string>"
}