See the related questions What computing resources are available on campus? and Is free software available or is a computer included?
There is no institution-wide requirement at this time for a student to purchase specific hardware or software. However, individual programs of study might have requirements in this area (e.g., a recommended calculator for a mathematics course). If your program of study (e.g., art or music) involves a certain kind of device or software, it might be advantageous to consider purchasing the same for yourself (but not required). Check with your adviser or program chair for details.
If there are no requirements for hardware or software, you are free to select a computer and software that best fits your needs and budget. Any modern computer or tablet should work on the Concordia University network. If you are considering a laptop or tablet, it might be worthwhile to see if there is an extended warranty, what it covers and how the service is provided (e.g., shipped for repair, taken to a local service center or on-site service). Portable devices tend to encounter more abuse than desktop computers, and an extended warranty can help mitigate an unexpected, costly replacement. Some credit cards double the warranty period of a purchase, and home owner’s insurance might cover some incidents.