  Methods.We applied distinct selection criteria to attain an SFG sample with
minimal AGN contamination. Multiple approaches were used to estimate the
intrinsic extinction, SFR and gas-phase metallicity for the SFGs. In
conjunction with findings in the literature, we examined the correlation
between SFRs and stellar masses ($M_*$), as well as the metallicity evolution
depending on $M_*$. Finally, the 3D relationship between $M_*$, SFR and
metallicity, is also studied.} Results. From the initial spectroscopic sample
of 409 FIR-selected objects from the Lockman--SpReSO catalogue, 69 (17\%) AGNs
have been identified and excluded, which is nearly double the percentage found
in local studies, leaving a sample of 340 SFGs. The analysis of the $M_*$--SFR
relationship revealed that Lockman--SpReSO IR-selected SFGs show signs of
evolution at redshifts $z>0.4$, shifting above the main sequence, with a mean
value of $\sim0.4$ dex. They are located within the starburst galaxy region
since 78\% of the galaxies fall into this category. In addition, no evident
flattening was found in the relation to specific SFR with redshift for $\log
M_* (M_\odot) \gtrsim 10.5$. In line with the $M_*$--metallicity relation (MZR)
outcomes published in previous studies for optically selected SFGs, however,
during the analysis of the MZR, it was found that IR-selected SFGs exhibit
lower metallicities than those anticipated on the basis of their $M_*$ and
redshift. During the investigation of the 3D $M_*$--SFR--metallicity relation
(FP), it was established that the research sample is consistent with relations
in the existing literature, with an average scatter of $\sim0.2$ dex. However,
a re-calibration of the FP when using the SFR obtained from the IR luminosity
is required and, in this case, no attenuation in the correlation for $\log M_*
(M_\odot) \gtrsim 10.5$ is observed.
