If each random variable $X_i$ has a concentration then when does average of $X_i$, sampled iid, also concentrate?

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I was reading this paper. I saw a fascinating Proposition.[Page-5 of that paper] enter image description here

Now I have my $X$ as this which are not subgaussian. Can I get something like proposition $1.2$ for my non-subgaussian $X$?

$$\mathbb{P}\left(|(h_{w}\left(s_i,p_i\right)-\mathbb{E} h_{w}) z_i| \geq 2B \cdot C_{\beta, D_{L S_\beta}} m(\xi,h_{w} )\right) \leq e^{-\xi}\tag1$$

Let, $$X_i = (h_{w}\left(s_i,p_i\right)-\mathbb{E} h_{w}) z_i$$

$$\mathbb{P}\left(|X_i| \geq 2B \cdot C_{\beta, D_{L S_\beta}} m(\xi,h_{w})\right) \leq e^{-\xi}\tag2$$

$$ \mathbb{P}\left (\frac{1}{n}\left| \sum_{i=1}^n (h_{w}\left(s_i,p_i\right) - \mathbb{E}[h_w])z_i\right| \geq Constant \right ) \leq e^{-\kappa}\tag3$$ $\quad put \quad \xi = \kappa \quad and \quad thus \quad 2B \cdot C_{\beta, D_{L S_\beta}} m(\kappa,h_{w} ) = Constant $


How Can we write (2) to (3). Is it possible?