Does the moon change its shape by turning?

NO!!!

The Moon like the Earth, is always turning(rotating)

The Moon changes its apparent shape because of its position relative to Earth and Sun.

As a line position.

Sun = Moon = Earth (New Moon ; not seen except at Solar Eclipse)

Sun= Earth=Moon (Full Moon ; round bright disc.

Sun= Earth ¬ ( Moon a right angles to Earth) the Quarter phases.