Shirk leads to hell fire:

Shirk is the greatest sin that Allah will never forgive:so
Worship the creator Allah but don't worship the creation Jesus 
And the death people 
And graves 
And idol 
And Shirk leads to hell fire:

The Qur’an says in Surah Ma’idah:

"They do blaspheme who say:
‘Allah is Christ the son
Of Mary.’ But said Christ:
‘O Children of Israel! Worship Allah, my Lord
And your Lord’. Whoever joins other gods with Allah –
Allah will forbid him the Garden, and the Fire
Will be his abode. There will for the wrongdoers
Be no one to help."

[Al-Qur’an 5:72]

Worship and Obedience to none but Allah:

"Allah forgives not

That partners should be set up
With Him; but He forgives
Anything else, to whom
He pleases; to set up
Partners with Allah
Is to devise a sin
Most heinous indeed."

[Al-Qur’an 4:48]

"Allah forgives not

(The sin of) joining other gods
With Him; but He forgives
Whom He pleases other sins
Than this: one who joins
Other gods with Allah,
Has strayed far, far away
(From the Right)."

[Al-Qur’an 4:116]

"O men! Here is
A parable set forth!
Listen to it! Those
On whom, besides Allah,
You call, cannot create
(Even) a fly, if they all
Met together for the purpose!
And if the fly should snatch
Away anything from them,
They would have no power
To release it from the fly.
Feeble are those who petition
And those whom they petition!"

Al-Qur’an 22:73]