A new moon is a phase of the moon in which none of the moons face is visible and else is dark. A lunar eclipse occurs when the moon passes through the shadow of the Earth, temporarily darkening its surface. So the main difference in the new moon the surface of the moon is permanent dark because of the light of the sun whereas in the lunar eclipse, it is dark temporarily because of the earth comes exactly between the sun and the moon.
A New Moon is one of the eight phases of the Moons cycle, whereas a lunar eclipse is when the Moon moves between the Earth and the Sun, this is a lunar eclipse.
New moon means when there is a birth of new moon it occurs after 29 days and lunar eclipses means when the moon is come in middle of earth and sun. Through this the sunlight doesn't reach to earth that's why the sun look dark.