Interview for my dream job involves a swim test and I'm already assuming I'll fail

I was invited to take part in a swim test for my dream job at an animal care facility where I'd be working to rescue and rehabilitate marine wildlife. It's kind of a risk - it's part time but I have some savings and nothing to lose.

The only thing is that the job involves a basic swim test. The facility has other very intense tests for trainer positions, but this one is more in line with a lifeguard test.

My immediate reaction is that I'd never be able to pass it. And it's so frustrating. it's very, very possible to pass and yet I'm so limited in how I view myself. I'm currently unemployed and the test isn't until November 16th. That's a decent amount of time to hit up the pool to practice.

DAE struggle with the limiting mindset? How do you break out of it? It's followed me wherever I go and I don't know how to push past it.

Swim test:
* Freestyle swim (approx. 150 feet)

* Underwater swim with one breath (candidate swims as far as possible underwater)

* 12. ft surface dive, retrieve brick from bottom

* Tread water for 5 minutes

* Pull yourself out of the water to your feet

* 30 second public speaking (script reading)

* An upper body strength test will be conducted once all in-water portions are complete. The candidate will carry two large metal buckets full of water a short distance, lift them into a golf cart, take them back down, and walk another short distance with the buckets