What must be considered is the graphical design software you will be using.
Most software applications list the necessary hardware and OS requirements.
Likely in some form of "minimal", "recommended", and "best".
You do not want "minimal" and you do want as much "best" as you can afford.
An i5 may "do the job" but performance could be slow. The same holds true for other components as well.
Slow performance is not helpful when trying to crunch through an important lesson or project.
Who is "they"? If instructors, advanced students, technical support, then I would purchase an i7 with at least 8 GB.
If your budget is tight, ask around: you may be able to get the laptop and/or software via a student discount. Or maybe purchase from another student who is graduating or otherwise no longer in the program.