When you buy a Xmas tree, the trick is to buy one with its roots still attached.
Then you just shove it in the garden.
You might still be able to get one, check your garden centres.
From seed, it takes about 2 years to get established and then up to 2 years per foot. Ie a 6ft tree will take around 14 years. That's why they cost.
Then you chop it down, bring it inside and two/three weeks later, you pulp it,