Does it mater which term goes first in a ratio, explain

Yes, the first term applies to the the first term in the statement, so for example,

'The ratio of apples to oranges in the box is 2:5'

The 2 applies to the apples, and the 5 applies to the oranges.

If the question was misread, it could be interpreted as 5 apples to 2 oranges, which is wrong.

Yes it all depends on the question if it says there is 12 potatos and 5 tomatos what is the ratio of tomatos to potatos you have to make sure you put tomatos first