Mūla — the verse
Gita Press numberingयदृच्छया चोपपन्नं स्वर्गद्वारमपावृतम्।
सुखिनः क्षत्रियाः पार्थ लभन्ते युद्धमीदृशम्
yadṛichchhayā chopapannaṁ swarga-dvāram apāvṛitam
sukhinaḥ kṣhatriyāḥ pārtha labhante yuddham īdṛiśham
Anuṣṭubh(!!) irregular in source
Translation
Swami Gambhīrānanda · follows Śaṅkara-bhāṣyaO son of Partha, happy are the Kshatriyas who come across such a battle, which presents itself unsought and is an open gate to heaven.
हिन्दी अनुवाद — Swami Tejomayānanda
और हे पार्थ ! अपने आप प्राप्त हुए और स्वर्ग के लिए खुले हुए द्वाररूप इस प्रकार के युद्ध को भाग्यवान क्षत्रिय लोग ही पाते हैं।।
Pronunciation — Vaamshii
from Vaamshiiयदृच् छया चोप पन्नम् (!!)
स्वर्गद् वार मपा वृतम्
सुखिनः(ह) क्षत्रिया# पार्थ
लभन् ते युद् ध मीदृशम्
॥ ३२ ॥
Read each split group as one breath-unit; hyphens join pādas kept whole for the meter or a compound word. Symbols: # upadhmānīya (visarga before p/ph), % jihvāmūlīya (visarga before k/kh), ऽ avagraha (an elided a). Full method →
Word by word
padārthayadṛichchhayāunsought
chaand
upapannamcome
swargacelestial abodes
dvāramdoor
apāvṛitamwide open
sukhinaḥhappy
kṣhatriyāḥwarriors
pārthaArjun, the son of Pritha
labhanteobtain
yuddhamwar
īdṛiśhamsuch
Meaning — Questions & Solutions
from Q&A with KnA2.32What kind of battle does Kṛṣṇa call an open door to heaven — and for whom?
O son of Partha, happy are the Kshatriyas who come across such a battle, which presents itself unsought and is an open gate to heaven.
The verse itself, in Swami Gambhīrānanda's rendering, is the answer. For reasoned solutions to knotty verses, browse the Q&A index.