You can open an order as much as you like. It has not limit in opening a trades not unless you have an insufficient balance on your trading account?

There is no restriction in placing an order as long as you have enough trading balance.

Many times. There is no limit in placing an orders as long as you have sufficient trading balance on your account. If you have no enough money, it's better to deposit more funds on it to have a limitless entry.

It's no limit for placing an orders in forex trading, it depends on your trading balance.