Any general point on the line is $\left(2\lambda +\mathrm{2,} 2\lambda -2, \lambda +1\right)$

This point most satisfy $x+y+z=21$

Hence $2\lambda +2+2\lambda -2+\lambda +1=21\Rightarrow \lambda =4$

So, the point of intersection of line and plane is $(10, 6, 5)$

So, equation of plane P = 0 is $2\left(x-10\right)+2(y-6)+1(z-5)=0$

$\Rightarrow 2x+2y+z-37=0$

Hence, distance of $P=0$ from origin is

$=\left|\frac{37}{3}\right|=\frac{37}{3}$