  Van der Waals (vdW) ferromagnets are an important class of materials for
spintronics applications. The recent discovery of atomically vdW magnets
CrI$_3$ and Cr$_2$Ge$_2$Te$_6$ has triggered a renaissance in the area of
two-dimensional (2D) magnetism. Herein we systematically studied
2H-Mn$_{0.28}$TaS$_2$ single crystal, a 2D vdW ferromagnet with $T_c$ $\sim$
82.3 K and a large in-plane magnetic anisotropy. Mn $K$-edge x-ray absorption
spectroscopy was measured to provide information on its electronic state and
local atomic environment. The detailed magnetic isotherms measured in the
vicinity of $T_c$ indicates that the spin coupling inside 2H-Mn$_{0.28}$TaS$_2$
is of a three-dimensional (3D) Heisenberg-type coupled with the attractive
long-range interaction between spins that decay as $J(r)\approx r^{-4.85}$.
Both resistivity $\rho(T)$ and thermopower $S(T)$ exhibit anomalies near $T_c$,
confirming that the hole-type transport carriers strongly interact with local
moments. An unusual angle-dependent magnetoresistance is further observed,
suggesting a possible field-induced novel magnetic structure.
