wearing silk

Q: Can men wear clothes made of artificial silk fabric?

Q: Can I wwear a sherwani which has brocade work on it? (Brocade is a class of richly decorative shuttle-woven fabrics, often made in colored silks and with or without gold and silver threads).

I already purchased it and its hard to return. I asked the worker if it contains silk, he told me that it doesn't contain silk. Can I wear it on my nikaah? 

Q: Is it permissible to wear boski material for men?

Q:

1) I heard many times from many people that if you satisfy your sinful desires in this world like drinking wine, wearing silk etc, these desires will be taken out from you in Jannah, is that true?

2) I thought even if you commit sinful acts or desires like drinking wine, wearing silk, if you repent you are forgiven so if you repent would Allah still take away these desires from you?

3) What worries me that if I drank wine, wore silk clothes, ate on gold plates etc I wouldn't do these things in jannah (paradise), if I committed those things, if I repent would that be enough?

4) Does Allah forgives sins if you repent without namaaz?or you have to pray namaaz to get your sins forgiven of drinking wine, wearing silk clothes?