It's kind of a weird question to ask about $2.3m on a forum. But in case you're serious:

- Most of the tokens are probably best exchanged against ETH on decentralized exchanges like IDEX or Uniswap. Look out for the exchange with the highest liquidity (typically, traded volume) for the specific token at hand
- It makes sense to try with a smaller chunk at first. I understand you want to exchange for fiat, so Coinbase is a good address to start
- Even if Coinbase works for you, you might want to use multiple fiat-capable exchanges to get rid of that large amount. Depending on where you are located, BitStamp, Kraken, Gemini or Bitcoin.de could be options