My battery health is very bad performance

Battery Health cannot be recovered. Every time you charge your iPhone battery, it's battery health will decline little by little. There is no battery known to mankind which doesn't lose it's ability to hold the same charge it did when new as it ages.

If your battery health has not dipped to 80% or below, your battery is doing OK. When its health dips below 80%, it will be time to pay Apple to replace the battery.