The questions about possible careers are big questions!! I'm not 100% sure this sub-reddit is the best place to ask them tbh. My first piece of advice would be to seek out physiotherapists/pharmacists/optometrists in your extended social/family groups, and ask them these questions. Even better would be if you can shadow them for a day or something. Nothing replaces firsthand experiences when it comes to making these types of decisions.
Regardless, I will try and answer some of these questions, but take what I say with a grain of salt, as this is just my opinion and I experience everything through my unique perspective/background.
I am a physiotherapist and have worked as one for about 7 years. I am currently applying for medical school. I have many friends who work in a broad spread of healthcare professions.
The first question I would ask you, is what do you want from a career? You seem to be very focused on employment opportunities. This makes up just one component of your career. What else do you value in your search for a career? Lifelong learning? Long-term progression? Autonomy? Work/life balance? Business ownership? Stress levels? Salary levels? The list goes on and on. If I was you, I would turn your focus away from 'job opportunities', and start looking at other components of these careers, and compare them with each other and with medicine. Healthcare is a very stable area of employment. In my experience, all four of these professions are in high demand, and you can find a job if you are willing to be somewhat flexible.
Again, the best thing you can do when trying to answer these questions is to find honest and open professionals in these fields and ask them questions. If possible, find people that have somewhat similar values to yourself, so that their opinions may mirror yours more closely.
As for maintaining a high GPA during undergrad? I can't help you hahah. My physiotherapy undergrad GPA was 5.2 (GEMSAS 5.9). But I have completed a Masters now with a GPA of 7, and I'm sure the approach would be similar:
- Prioritise your study
- Be organised, plan ahead, start assessment early and work on it over weeks rather than cramming
- Read widely, especially the recommended readings that are suggested by your lecturers/tutors
- Find youtube videos that explain concepts, and add visually to your understanding of them
- Engage with your lecturers, tutors, and peers online and in-person, this helps to cement/test your knowledge
None of these are very unique, and I don't think there is any 'trick' to getting good marks. Just be organised, engaged, and start assessment early. I have been privileged enough to be able to only work 2 days a week as a physiotherapist while I study, so I could make enough money to live, and have plenty of time to prioritise study. Other people are not as lucky, and as a result it is much harder to maintain good marks over the course of 1.5-4 years. This is the equality problem of using GPA in med school applications, those with stable socioeconomic conditions are in a much better position to do well at university, but they aren't necessarily better suited to being a doctor. But that's a whole other can of worms!
Anyway, hope there is something of value in this post for you! All the best!