The star-forming main sequence (SFMS) is a tight relation observed
between stellar masses and star formation rates (SFR) in a population of
galaxies. This relation is observed at different redshifts, in various
morphological, and environmental domains, and is key to understanding
the underlying relations between a galaxy budget of cold gas and its
stellar content. Euclid Quick Data Release 1 (Q1) gives us the
opportunity to investigate this fundamental relation in galaxy formation
and evolution. We complement the Euclid release with public IRAC
observations of the Euclid Deep Fields, improving the quality of
recovered photometric redshifts, stellar masses, and SFRs, as is shown
both with simulations and a comparison with available spectroscopic
redshifts. From Q1 data alone, we recover more than $\sim
30\,\mathrm{k}$ galaxies with $\log_{10} (M_\ast/M_\odot) > 11$,
giving a precise constraint of the SFMS at the high-mass end. We
investigated the SFMS, in a redshift interval between $0.2$ and $3.0$,
comparing our results with the existing literature and fitting them with
a parameterisation taking into account the presence of a bending of the
relation at the high-mass end, depending on the bending mass, $M_0$. We
find good agreement with previous results in terms of $M_0$ values, and
an increasing trend for the relation scatter at higher stellar masses.
We also investigate the distribution of physical (e.g. dust absorption,
$A_V$, and formation age) and morphological properties (e.g.,
Sérsic index and radius) in the SFR--stellar mass plane, and
their relation with the SFMS. These results highlight the potential of
Euclid in studying the fundamental scaling relations that regulate
galaxy formation and evolution in anticipation of the forthcoming Data
Release 1.