Im trying to avoid veterinary fieldwork. Also, an occupation that travels a lot and does more fieldwork than lab work.

I can’t think of any career where you would scuba dive to do medicine, because health care is never performed underwater.

You could be a doctor/nurse specializing in, among other things, treating divers who get decompression sickness. But you would never scuba dive to do that career.

Here’s a more general set of ideas about how to choose:

What do you like to pay attention to in your spare time? That might hint at careers you will enjoy. I say "enjoy" because that will help you be motivated and succeed.

Visit the different sections of a big book store, not just the stuff you already like. Look at a variety of magazines and books. See what grabs your interest.

You should try lots of things, because it’s not immediately obvious whether you will like a given activity; you have to give it some time before you know. Besides, having lots of skills and activities is valuable. Not only does that help you function in life, it also makes you a more interesting and valuable person to know. If you live an interesting and varied life, you will have lots to talk about when socializing.

If your school offers non-required classes in art, computer programming, etc, take those classes.

Maybe join clubs, at school or elsewhere, that exercise skills of some kind.

You should try various hobbies, even if you have no immediate interest in them.

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Then, during a school vacation, just before you must apply to colleges and trade schools, do the following:

Think back on the many kinds of activities you’ve tried in life.

What parts of those activities did you do especially well, whether or not you enjoyed them? Make a list.

What parts of those activities did you truly enjoy, whether or not you did them well? Make a list.

Your ideal job would use the maximum number of items from the two lists combined.

When I say "parts of those activities", I mean things like:
research – compiling facts from different sources
taking devices apart to see how they work
inventing or creating things
writing
talking to people, and figuring out how they think
figuring out how the physical world works
repairing things
and so on.

You also have to consider your personality and temperament. For example, do you need to completely know what you’re doing before you first attempt to do it, or are you comfortable just winging it? Do you like to be told what to do, so you don’t do anything wrong? Or are you creative and comfortable with confusion, ambiguity, and freedom of choice? Answering those questions lets you guess whether you are suited to any career involving creative effort (art, engineering, writing, computer programming, etc).

Search online for vocational/career test websites. Try them out. The efforts I described above will help you answer their questions.

That’s my quick-and-dirty career choosing system. If you want to explore more carefully, you can find entire books about the subject of career and job choice. See your local library or book store.

When you come up with some possible career choices, find books about each one, describing what it’s really like and what is really required to succeed. You could look at websites too, but I think books will be more thorough and better researched.

If you are still stumped, after all that research, I guess you could just choose any well-paying and recession-proof career at random. You are like many people, having no idea what career to choose, if that’s any comfort.

But you DON’T want to get this wrong, if you can avoid it. Otherwise, you might waste four years and money at a university studying the wrong thing, like I did.