so let say you are a good Muslim you prayer 5 times read the Quran and fast, but when its time for you to go. What will happen if you cant say the shahada like you died to quick or your throats injured?
Reciting the shahada is done either as an act of entering into of Islam or as a dhikr.
Saying the shahada once during life is what makes a person a Muslim. As long as a person accepted Islam once and then died without committing Kufr, they would be treated as a Muslim and they would enter paradise eventually and be saved from an eternity in Hell.
Repeating the shahada as a dhikr at the time of death is a recommended and virtuous act for one who is able (Muslim 917 , Abu Dawud 3116), but it does not change the status of a person. And there are several Muslims who die without getting this opportunity, such as those who die in their sleep - and they all still fall under the meaning of the other texts:
وعد الله المؤمنين والمؤمنات جنات تجري من تحتها الأنهار خالدين فيها
Allah has promised the believing men and believing women gardens beneath which rivers flow, wherein they abide eternally
ما من أحد يشهد أن لا إله إلا الله وأن محمدا رسول الله صدقا من قلبه إلا حرمه الله على النار
There is none who testifies sincerely that none has the right to be worshipped but Allah and Muhammad is his Apostle, except that Allah, will save him from the Hell-fire.
Not saying the sahahdah at the moment of death isn't as sign of a bad ending
First of all if the question is whether not being able to perform the shahadah is something bad for the life in the hereafter? Then the answer is no.
A Muslim remains a Muslim as long as he didn't commit shirk or kufr and what at the end of his life counts are his deeds. Secondly if one is not able to do something Allah the Almighty would know this better than any of His creation and His Mercy and Justness wouldn't allow to count something behind a servants possibilities as bad. Allah says:
Allah does not charge a soul except [with that within] its capacity. ... (2:286)
However in case of a choice there are levels of good and levels of bad deeds. The best is always what our prophet () taught us beyond Allah's orders and the worst is what Allah clearly forbid.
Saying the sahahda at the moment of death is a sign of a good ending
As stated in the hadith which was graded as sahih by some scholars, saying the shahadah at the moment of death is a sign of a good ending:
The Messenger of Allah (ﷺ) as saying: If anyone's last words are "There is no god but Allah" he will enter Paradise. (Sunan abi Dawod)
So this hadith only states one of the signs of a good ending (among many more) and one of the signs of entering Jannah (among many more) so its statement isn't to be understood as exclusive. End even if it was there would be special cases.
At the end whatever will let us enter Jannah is first Allah's endless mercy, secondly our good deeds.
Scholars used to say a good believer lives between two states: hope and fear: The hope of entering Jannah due to Allah's mercy and the fear of Allah's punishment.
Further some scholars regard it as a virtuous to exhort relatives to say the shahadah if one fears their death to be coming soon based on some sahih hadith (see in Sunan abu Dawod, Sunan ibn Majah here, here and here-qulified as da'if-, Sunan an-Nasa-i here and here, Jami' at-Tirmidhi, Sahih Muslim here and here . However there's a difference of opinion on this:
Some scholars say one should remind them, others would say it is one should say it in front of them in order that they repeat it or hear it and this or saying it when they have died instead of them is a strongly disputed topic.
See also islamqa fatwa #114666 (available in Urdu and Arabic).