If the software or coursework requires a dGPU the 13" is not a solution, although higher educational facilities can offer computer labs/workshops for this purpose. As long as the software will run on the 13" it will work, however processing will be much slower than the 15" as the 13" MackBook Pro only Intel integrated graphics and dual iCore CPU. I would suspect that the college/university will be able to advise a minimum specification for a laptop, as long as the 13" Mac exceeds this you will be ok, anything more is just nice to own & use.
Even the 13" price will escalate if you require additional storage, my own 2014 rMBP is the 512 SSD option, which is around 26,000 EGP ($3K US) for you. Likely you will need the 256 SSD minimum if you plan to run Windows due to software requirement.
A possible option that may work for you depending on the coursework is to purchase a base 13" MacBook Air for on the go, and put together a cheap desktop PC for the heavy weight work in the evenings. This would probably be as much as a mid to high 13" rMBP, however you would have a lot more processing power and still retain the Mac experience that you want. The only real downside is the Air`s TN display as the viewing angles are not as good as the Retina`s. Even a cheap desktop PC will offer far more performance than the average laptop, I doubt you will need a Workstation at your level, nor will you likely need the fastest components, think more what you need, not what you would like, as this will help to keep the budget down.
I appreciate your situation as I lived and worked in the Middle East for close to 3 years and the price of Mac`s was always extremely high (State of Qatar) with very little support. Unfortunately there are no easy solutions, as your not able to source a powerful Mac with dGPU at a reasonable price locally.
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