There are a number of Bitcoin practice networks where you can try out different things with coins that don't count. Testnet3 and Testnet4 are probably the most popular Bitcoin test networks, but they are not always reliable.

There is another kind of test network called Signet. Signets have all the same properties as normal Bitcoin except the coins are worthless and mining is permissioned (blocks must be signed by the operators of the network).

Sometimes it can be kinda difficult to get signet coins. If you've been looking for some, the people over at Liana Wallet are doing a giveaway. Check out the headline link if you're interested in acquiring some.