Add punctuation: The tree line further down the farther north one goes Birch forest mountain birch forest grows around the tree line
A: The tree line further down the farther north one goes. Birch forest: mountain birch forest grows around the tree line.

Add punctuation: The 3 scarce radiobuttons such as changing only the interval
A: The 3 scarce (radiobuttons) such as changing only the interval.

Add punctuation: Hi my name is sunkatt and I am 19 years
A:
Hi, my name is sunkatt and I am 19 years.