  In this paper we describe our search for galaxy protocluster candidates at
$4.5< z < 10$ and explore the environmental and physical properties of their
member galaxies identified through JWST wide-field surveys within the CEERS,
JADES, and PEARLS NEP-TDF fields. Combining with HST data, we identify 2948
robust $z>4.5$ candidates within an area of 185.4 arcmin$^2$. We determine
nearest neighbour statistics and galaxy environments. We find that high-$z$
galaxies in overdense environments exhibit higher star formation activity
compared to those in underdense regions. Galaxies in dense environments have a
slightly increased SFR at a given mass compared with galaxies in the lower
density environments. At the high mass end we also find a gradual flattening of
the $M_{\star}$-SFR slope. We find that galaxies in high-density regions often
have redder UV slopes than those in low-density regions, suggesting more dust
extinction, weaker Lyman-alpha emission and / or a higher damped Lyman-alpha
absorption. We also find that the mass-size relation remains consistent and
statistically similar across all environments. Furthermore, we quantitatively
assess the probability of a galaxy belonging to a protocluster candidate. In
total, we identified 26 overdensities at $z=5-7$ and estimate their dark matter
halo masses. We find that all protocluster candidates could evolve into
clusters with $M_{\rm halo} > 10^{14}M_{\odot}$ at $z = 0$, thereby supporting
the theoretical and simulation predictions of cluster formation. Notably, this
marks an early search for protocluster candidates in JWST wide field based on
photometric data, providing valuable candidates to study cosmic structure
formation at the early stages.
