$\newcommand\al\alpha\newcommand\be\beta$The answer is yes. Indeed, using the inequalities $u^\be\le\max(1,u)\le1+u$ for $u=f(s)\ge0$, we see that for $t\in[0,1]$ the inequality $$f(t) \le \al+ \int_0^t (t-s)^{-1/2} [f(s) + f(s)^\be] \,ds$$ implies $$f(t) \le \al+2t^{1/2}+2 \int_0^t (t-s)^{-1/2} f(s) \,ds.$$ It remains to use [Theorem 2.2][1]. [1]: https://ejde.math.txstate.edu/Volumes/2021/80/webb.pdf