Taking E with out a T blocker?

I recently got E injections ordered. And from my knowledge injections are fine to start with for first time user. But I recently got told by somone who's on E that if I don't take a T blocked it'll kill me. But I was also under the impression that E can suppress T if done right. I'm so confused rn. I don't have access to get a T blocker. Just I'm so confused