The collar is designed to limit excessive turning and bending of the neck. That is useful when movement makes discomfort worse, but it also affects everyday activities that require moving your head freely.
Driving: before driving, check whether you can turn your head far enough to see mirrors and blind spots. If the collar prevents that, driving may be unsafe. Also consider that sudden braking or evasive steering can move the neck in a way that feels uncomfortable. If a professional has not said it is safe, avoid driving while wearing the collar.
Sleeping: the product information does not describe it as a night-time support. Sleeping in a cervical collar can create unnatural pressure on the jaw or back of the neck, and it may twist the head during sleep. Unless a pharmacist or doctor advises wearing it at night, remove the collar before bed.
Work: this depends on what you do. If your work involves sitting at a desk or looking at a screen, the collar may be helpful because it can reduce the tendency to hold the head in a tiring position and may reduce the feeling of fatigue after long periods of poor posture. If your work requires bending, lifting or turning the head constantly, the collar may get in the way and should probably be worn only for specific parts of the day, based on professional advice.
In all cases, the most important rule is to let the purpose of the collar guide how you use it: it is meant to reduce excessive movement, not to make daily life harder. If an activity feels unsafe or uncomfortable, remove the collar and ask for guidance.