I grew a beard and I am wondering if it's haram. All my friends are telling me it's haram and I think they are right because they gave me good proof. Is it true?
According to the Sunnah we should grow our beards and trim the moustaches.
No. In fact, the Prophet had a beard himself:
It was narrated from 'Uthman that: The Messenger of Allah performed ablution and ran his fingers through his beard. -- The Book of Purification and its Sunnah (sunnah.com [grade: hasan] and sunnah.com [grade: sahih])
Other sahih ahadith are Abu Rimthah: "...he had dyed his beard with yellow dye" (sunnah.com) and Aishah: "I used to put perfume on the Messenger of Allah using the best perfume I could find, until I saw the perfume glistening on his head and in his beard, before he entered Ihram" (sunnah.com).
The Prophet in fact requested that others likewise grow theirs, although in a certain manner:
Narrated Ibn 'Umar: that the Messenger of Allah (ﷺ) ordered trimming the mustache and leaving the beard to grow. -- Jami` at-Tirmidhi [grade: sahih] (sunnah.com)
As such, concerns about men's beards usually go in the other direction, e.g. "Shaving the beard is haraam because of the saheeh ahaadeeth that clearly state this, and because of the general application of texts that forbid resembling the kuffaar." (Islam Q&A).
What makes you think beards are haram? Muslims are obliged to grow beards and not shave them . It is the sunnah and tradition of our Prophet.