well translated. few corrections.
kyon hum uljhein duniya se bekaar mein
Why are should we get tangled in world for no reason?
if line was uljhe then ur translation was accurate.
bekaar mein hum duniya se kyun uljhein?
But I’ve seen God in your eyes
par means 'but'
janam janam ke bandhan tujhse baandh liye hai
janam janam: beloved janam जनम is जन्म - birth; it is talking of this and forecoming lives(rebirths)
jaanam is beloved
ke bandhan: bonds (chains) of
tujhse: to you
baandh liye hai: (they) have chained
The bonds (chains) of beloved have chained you
line means that we are bonded(or accurately i have bonded with u) for this life as well as lives after this life.
kahaan kisi ki hogi jo taqdir hai meri
[…] the destiny that is mine
[...] where would anyone have (the destiny like me)
raanjhe ki uss hir se sundar hir hai meri
With the Ranjha´s elixir, the elixir of beauty is mine
heer is lover of raanjha.
my heer(beloved) is more beautiful than ranjha's heer.