Please

Start by getting a divorce

As Fred said.  Sorry to have to tell you but whenever expats get married in any GCC country, generally speaking, a letter of civil status is requested by the authorities from their respective Embassies i.e. whether they are single, married, divorced etc.  If you are already married and the Embassy shows that on the letter, you won't be able to do another marriage in Saudi.

Thank u for your advice ,it is not possible even we are both muslim ?

Are there any countries where it's legal for a married woman to marry a second husband before divorce?
The only difference between your country and Saudi is, as I understand it, they don't whip you or chop your head off for doing it back home.

The case is my iqama and passport is still single

If they find out, you could end up in very serious trouble.
As for your documents in Saudi, false information might well be grounds for arrest.

If the possibility of being whipped, maybe even beheaded, doesn't make you think it's a bad idea - go ahead and get married.

No i dont want that to happen,
But why they are some saying ,if they ask permission or hand writing permission from husband that letting the wife to get marry again ,its that true?

Yes, that exists - it's called a divorce paper.

But the divorce in philippines is not legal now its on the process to be legal ,that consent is only hand writing and notarize from lawer ,that mean the ex husband let the wife to marry and he will never file any case to the wife.

Yes, divorce isn't legal for you and you can't get married without a divorce, so you either forget it or risk whatever punishments the Saudi courts decide upon if you're found out.
Given being whipped is likely to be rather unpleasant and beheading (If you're really unlucky and they add witchcraft or something) tends to ruin your hairstyle, it's probably best to forget it.