Greetings AvarAllahNoor,
The verses in question are:
O you who believe! Whoever from among you turns back from his religion (Islam), Allah will bring a people whom He will love and they will love Him; humble towards the believers, stern towards the disbelievers, fighting in the way of Allah, and never fearing the blame of the blamers. That is the grace of Allah which He bestows on whom He wills. And Allah is All-Sufficient for His creatures' needs, All-Knower.
Verily, your Protector is Allah, His Messenger, and the believers, those who perform the Salah, and give Zakah, and they bow down.
And whosoever takes Allah, His Messenger, and those who have believed, as protectors, then the party of Allah will be the victorious.
[Qur'an, 5:54-56]
Now, this is proof that Sikhism is the religion revealed by God. Sikhs have the Khalsa, which is arabic for pure. - It states in the Kuran.
The verses that you quoted do not support this argument in any way, as is clear from the context. In fact, this is clear from the Qur'an as a whole. Many verses can be mentioned here; verses about Allaah perfecting Islam, naming us Muslims, accepting only Islam, about the finality of Prophethood and being the best nation raised up for mankind. And we haven't even looked at hadeeth, yet already so many contradictions to what you have asserted.
But looking at the verse, what gives the impression that it is referring to a whole new religion? It is simply threatening to replace the believers with another people if they revert from Islam. If we look to a source that actually has some credibility, such as a scholar of Islam and exegete of the Noble Qur'an, Ibn Kathir says:
Allah emphasizes His mighty ability and states that whoever reverts from supporting His religion and establishing His Law, then Allah will replace them with whomever is better, mightier and more righteous in Allah's religion and Law. Allah said in other Ayat,
(And if you turn away, He will exchange you for some other people and they will not be your likes.) and,
(Do you not see that Allah has created the heavens and the earth with truth If He will, He can remove you and bring (in your place) a new creation! And for Allah that is not hard or difficult.)[14:19-20]. Verily this is not difficult or hard on Allah. Allah said here,
(O you who believe! Whoever from among you turns back from his religion...) and turns back from the truth to falsehood, from now until the commencement of the Last Hour.
Your (real) friends are (no less than) Allah, His Messenger, and the (fellowship of) believers,- those who establish regular prayers and regular charity, and they bow down humbly (in worship).
Sikhs do this.
Sikhs might give charity and pray, but that does not mean they worship Allaah and take Muhammad (peace be upon him) as a Prophet. Going back to Ibn Kathir:
(those who perform the Salah, and give the Zakah...) referring to the believers who have these qualities and establish the prayer, which is one of the most important pillars of Islam, for it includes worshipping Allah alone without partners. They pay Zakah, which is the right of the creation and a type of help extended to the needy and the poor...
(and they bow down,) means, they attend the prayer in congregation in Allah's Masjids and spend by way of charity on the various needs of Muslims.
Peace.