I don't know

[Achebe]

cute poem. some issues with missing articles, etc. pointed out below.

I don’t know how to tell you this.
You, the embodiment of cuteness,
With smile, you crumble the darkness,  .....with a smile. 'slay' or 'melt' more appropriate than 'crumble'
With care, you can melt even the north pole. although you're trying to say 'with the care that you show towards me / other people', using 'with care' as a shorthand is not how you'd go about it. 'With care' can mean other things (eg. with attention, with worries, etc.). Best to carry on from the previous line eg. 'with a smile you slay the darkness, warm the winter, melt the poles.'

I don’t know how to tell you this.
I have been loving you since we met.
It is wrong, they said.
She has a boyfriend, they opposed.


I don’t know how to tell you this.
I envy the guy you love.
Just be him for one day, I wish.  .....to just be him
To hold you tightly, to be loved by you.


I don’t know how to tell you this.
Impossible, unfeasible, I notice.  .....infeasible. The "I notice" makes no sense.
Like two poles of magnet, we attracted. .....poles of a magnet, we attract
Like oil and water, we can’t mix.


I know how to tell you this.
I love you with all my heart.
I care for you with all my feeling.
I truly wish the world for you.