Can anyone tell me what this means please? I think it is a proverb
From Tao Te Ching ("Canon of morality") attributed to Laozi. These words are excerpted from various parts. Various translation exists, and here I am just being literal.

上善若水。水善利萬物而不爭。(part 8)
The utmost goodness [or benevolence] is like the water. Water is good at being benevolent to everything, and does not compete with them.

守靜篤。(part 16)
It is concrete to hold stillness.
[or better, "Surely you must be calm."

靜爲躁君。(part 26)
Stillness is the monarch of the movement.
[Or better, "The waiting person rules the impatient person."]

清靜為天下正。(part 45)
Stilness is the right thing of the world.
[Or maybe "Inactivity is the principle of reigning."]

It seems your friend admires Lauzi very much ; )