During live trading, yes, your broker plugin will update the Balance and Equity values. (Unless you override this behavior using the SET_PATCH broker command.)

Now, if you want to simulate it in a backtest instead, manually changing the Balance value does not work. Instead, consider applying credits and debits to your account using enterTrade(). I explain how to do this on my blog:
https://www.vitaltrades.com/2020/07/14/adding-exact-fee-and-credit-calculations-to-zorro/