Most of these sentences are grammatically correct, but the paragraph (as a whole) seems awkward. This is how I would write it:

My job

I currently work as an assistant in an animal hospital. I love my job, since I'm really into animals and I like to interact with them; compared to human beings, they're much easier to deal with.

Like a nurse, I mainly take care of animals and help the veterinarian conduct checkups. Sometimes, I deal with aggressive dogs or cats, and I have to protect myself. It's common to have scars on my body but despite this, I'm still crazy about animals. I believe that it's my lifelong career.

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my job