As far as engineering is concerned. College coursework doesn't have any great demands for computer hardware. I'd focus more on battery life, screen quality and portability. An SSD would make for a nice performance boost. If he doesn't need a lot of storage space.
Does he like Apple? The Macbook Air is one of the few laptops with an SSD in your budget. It's a nice computer with excellent battery life and excellent screen. Most college students love Macs.
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/www.amazon.in/Apple-MacBook-Air-13-3-inch-Integrated/dp/B073Q5R6VR/
The HP x360 is a great option. They are well regarded for their portability, and battery life. The CPU is decent enough with a 7th Gen Core i3 7100u. It does have dedicated graphics with an nVidia GeForce...