Doubt about Liquidity

Hi, I understood the basic concepts about ERC20 and what it concerns. But I have some doubts about the concept of liquidity, and liquidity pool.
So, if I want to deploy an ERC20 token, I have to provide liquidity (so I have to pay a lot of money) in order to allow exchanges. Is it correct?

but it seems strange to me, because, how can I provide so much liquidity? Every existing token did this? it would be an incredible expense, I think.

thanks to anyone who can clarify my doubts ^^

I think if you want to swap token, you can add liquidity in a decentralized exchanges, for example, you can add the liquidity of Your_Token and ETH in the Uniswap, then users can buy and sell. Or you can use the centralized exchanges, but you need to set the price of the orders.

Yes, but for example in Uniswap, I have have to provide liquidity just for setting the price or I have to spend much more? Sometimes tokens have millions of dollars of liquidity…but where all this liquidity comes from?

The first one who add liquidity will decide the price, eg: if you add 100 Your_Token and 10 ETH to the uniswap, that means 1 Your_Token almost is equal to 0.1 ETH, but actually, you can not swap 1 Your_Token to get 0.1 ETH, cause the volume is too small, so it will have a large slippage, so in order to keep a low slippage, expect to add large liquidity, so the liquidity can be millions of dollars.

And you can find some articles about uniswap to learn more.

Have I made myself clear?

Thanks, you are helping me understand a lot of things.

So, is it possible to release a token, and providing it a small quantity of ETH (the equivalent of 20$ for example) or would that be too small?
Another question: as people trade, does liquidity increase?

Yes, you can, but you should be noticed that, if the volume is small, when swap tokens, the slippage will be large.

Emmmm, I am not sure, cause the amount of one token decreases and the amount of the other one increases, so does liquidity increase? maybe, cause the protocol will charge some fee.