Confirmation means that the transaction has been processed by the network and is highly unlikely to be reversed. Transactions receive a confirmation when they are included in a block and for each subsequent block. Even a single confirmation can be considered secure for low-value transactions, although for larger amounts like $1000, it makes sense to wait for 6 confirmations or more. Each confirmation exponentially decreases the risk of a reversed transaction.
In most cases, Freewallet asks for 10 network confirmations (3 for BTC wallet). It usually takes about 20 minutes to finish a transaction. You’ll have a progress bar under your transaction to inform you about your transaction status.