What paint am I looking for?

[NutellaWithEverything]

If I want this type of green for my adult son's bedroom?

Find a sample of the colour you want and take it to a place that mixes the paint to match the sample. I have a very similar colour on one of my walls and had it mixed to match a fabric sample at B&Q, it was Valspar paint.

Olive green?

https://www.dulux.com.au/colour/greens/olive-leaf/

Farrow and ball Green Smoke is nice. Just done a whole room out in it.

We just redid our bathroom with coat paint and it's lovely to work with and wearing well. They do stick on samples but this green also looks close: coatpaints.com/products/mansard-flat-matt?slv_rt=v1%7E1huqbt5km%7E225f1d31-ba91-4214-b3c5-632821131c0d%7E270d5cf4-9996-4504-8a04-dcf0b9cac841%7E-u09qe4

I've just had my dining room done in this, it's great quality. www.duluxheritage.co.uk/en/colours/1780039/waxed-khaki