The ethereum network has been live since 2015. Since then, new "blocks" of ether (ETH), the native currency of the ethereum network, are being mined around every 15 seconds. A new block means new ETH being "minted," and entering circulation on the ethereum network.
The amount of ether that is minted in a block varies, depending on several variables, but is around 1 or 2 ETH, and works out to about 1,350 ETH per day (again, this amount may vary).
As of June 2023, the total amount of ETH in circulation is around 120,210,000.
Screenshot taken from https://etherscan.io/chart/ethersupplygrowth
Unlike bitcoin, which has a hard cap on the total supply that will ever be mined (21 million), the supply of ETH is potentially infinite. It is possible that future revisions to the rules of ethereum will modify the block reward and block difficulty, which would result in changes to the future supply of ETH.