Pick your POV and stick with it
When I started out writing, I had no idea what POVs were out there (or even what POV meant—point of view). By instinct (and by habit, from reading other books) I chose 1st Person for my first trilogy (closest to journaling), then 3rd Person Limited for Rosehead, and so on.
Once you pick your story's POV, you’re stuck with it, so study it to decide which one fits your story best before you start writing.
Switching to a different POV in the middle of your draft is a pain in the butt. I can tell you that from experience. Been there, done that.
There are tons of great books and online resources to study POV. My favorite is the very short but very informative book by Ursula K. Le Guin, Steering the Craft. It also has POV exercises which I’ve done and which I highly recommend you do, to practice different POVs before deciding on one.
What I like about POVs is that they can allow you to fix seemingly unfixable things.
For example:
If your book is too long, consider 3rd Person Objective POV (Le Guin calls it "Detached Author"), which is basically just a camera showing the action, with no character thoughts at all (as opposed to 3rd Person Omniscient which knows everything anyone ever thinks).
If you’re having trouble with world building, or are unsure how to make your fantasy believable (especially when starting out), consider 1st Person POV. This way whatever your Hero experiences is legitimate, and you don’t have to explain it except how you yourself would’ve reacted to a strange new world if you were in your Hero’s shoes.
If you want your story to expand, to get longer (a common problem with first novels is that they're too short), consider 3rd Person Omniscient. It'll add volume, but it'll also require you to know your story intimately, to know everything about everyone at all times.
If confused, read the book I recommended above and do the exercises. They'll help you pick the right POV.