You were tasked with guarding the Sihang Warehouse, and you brought out a Tiger tank?

[Battle of Shanghai Opening] + [Nanjing Breakout] + [Subsequent Main Battlefield] + [Troop Production System] + [No Romantic Drama] + [Weapons and Equipment with Illustrations]
(This is not a purely beginner's book; you can actually learn something from it. The rating is newly released, so it's a bit low; the older book has a guaranteed 9.0 rating.)
In 1937, Lin Feng transmigrated into the body of a ragtag security regiment commander in Zhejiang Province, starting his life in a prison cell in a bandit's den.
The system is bound to you; killing enemies will generate troops.
During the Battle of Shanghai, he was assigned to defend the Sihang Warehouse. His superiors ordered: "Hold on for a week and show your fighting spirit!"
Lin Feng glanced at the vehicle purchase permissions that had just been unlocked in the system and nodded.
He held on on the first day.
The next day, he retaliated.
On the third day, the Japanese soldiers on the outer perimeter were bewildered: "Reporting to the colonel, the garrison at Sihang Warehouse... seems to have an extra battalion compared to yesterday? And they have anti-tank guns that we've never seen before."
On the fourth day, a foreign journalist in the concession, peering through binoculars, screamed: "My God! What's that driving out of that building? A heavy tank?!"
Upon hearing the report, Japanese Army Minister Sugiyama Gen's hand trembled: "Where did this Lin Feng come from? Investigate where his troops and equipment came from."
Looking at his ever-growing army and the higher-level permissions that were about to be unlocked in the system, Lin Feng scratched his head: "I just wanted to guard a warehouse and kill a few more Japanese devils... How did I accidentally become an army group commander?"
The Japanese headquarters trembled as they marked the top-secret document: "The biggest variable on the Great Xia battlefield—Lin Feng's unit, unit number unknown, troop strength unknown, equipment increasing with each battle, extremely dangerous!"