When Sikhs worship, the head should be covered, after the worship is over, there is langar(community Kitchen) at Gurudwara(sikh place of worship), there is singing of hymns from holy scriptures.
No
Sikhs are individuals like everybody else. Some has allergies and others don't. There are no allergies specific to all Sikhs.
They learn like everyone else
Hindus, Buddhists and Sikhs believe in reincarnation.
they respect everyone else by being quite and listening to one another.
To remind them to don't have sexual intercourse with someone else that is not your husband or wife
The biggest disadvantage of worshipping in different ways, is that as soon as people have options, someone is bound to claim that their way is better than someone else's and create drama, fighting, sectarianism, hatred, violence and fear.
Sikhs have gurudawaras
Sikhs is not real
Since the meetings are of Sikhs, so usually Sikhs are present there.
Yes Sikhs have weddings.
Sikhs join the Khalsa.