Offset can mean a few things but for most discussions around here it means the address in the file.
The left hand column is the address, the middle is the file contents rendered in hex and the right the text (usually ASCII) conversion of the hex.
0x0014 just means 14h, or go to 10, count along 4 (hope you can think in basic hex for when you get 1A though 1F, though you have the numbers at the top above the hex contents as well). If you want to click on it then usually at the bottom will be an indicator of where the cursor is and you can hopefully also use context in whatever guide you are following (if you want to then save, export that, change how much money you have in game, export that and compare the two, should have changed by whatever amount of you changed by).
Framing something as "lines" is not really something that is done or encouraged -- while many do like a 10h/F wide window such that it counts 0,10,20,30,40... then not all editors will do this all the time and you might even want to change it yourself for some things if the data sections are a different size (usually less for most ROM hacking purposes) to that as that will make the data visually pleasing (or at least able to be navigated easily with arrow keys).
You might also encounter it as a relative position/jump. That is to say "what is before it can be various lengths but when you find this one thing the bit you want is [blah] away". Pointers might also be described as this -- text engines might start counting when the text starts rather than from the start of the file. It can also be done to allow people to edit different saves* within a file, though here it appears export handles it.
*backup saves might also do this -- pokemon used to quite famously alternate between save slots (how it does the save corruption detected, reverting to previous version thing) so rather than having to either write two guides, ignore the second slot or get people to do maths to figure out which thing they are supposed to be editing you might get that.
