Lp$$ {L}^p $$ estimates for the fractional Φ$$ \Phi $$‐Laplacian operator defined in bounded domains are established, where the nonlinearity is subcritical or critical in a suitable sense. Furthermore, using some fine estimates together with Moser's iteration, we prove that any weak solution for fractional Φ$$ \Phi $$‐Laplacian operator defined in bounded domains belongs to L∞(Ω)$$ {L}^{\infty}\left(\Omega \right) $$, under appropriate hypotheses on the N$$ N $$‐function Φ$$ \Phi $$. Using the Orlicz space and taking into account the fractional setting for our problem, the main results are stated for a huge class of nonlinear operators and nonlinearities.