Okay, let's take this step by step. Because what we have here is a type of treasure hunt (as per the title) more commonly known as:
an imgur maze - i.e. a treasure hunt built of a series of images stored on the file-sharing site imgur, where the answer to one is the URL for the next.
The diagram at the bottom of the puzzle depicts:
The letter keys of a computer keyboard (standard QWERTY layout - 10 on the top row, then 9, then 7). If we take the letters indicated by the numbers and in numerical order, using the larger, 'bolder' numbers as indicating upper-case letters and the others lower-case, we get the letter sequence KYFezJS.
How do we know what to do with this? Note that:
the last line of the note mentions 'image' and 'err', which can be associated with 'imgur', the file-sharing site. Also, 'slash a slash' is not nonsensical - it's a vital part of the web address, as we will next need to insert '/a/' before the 7-character code to let us navigate to https://imgur.com/a/KYFezJS/.
What do we find here? Another treasure hunt puzzle!
So let's solve it...
- The egg of a Canadian bird = '0' (My logic was that Canada geese lay pretty large ovoid eggs, so '0' most closely resembles their shape - however, the OP's intention was that 'goose egg' is a slang term for zero);
- Really loud comic snore = 'Z' (Z's are commonly used in cartoons to indicate snoring, a loud one would be capitalised);
- A tiny kiss = 'x' (As on a text or birthday card - lower case, since 'tiny');
- The little part of copper = 'u' (The Periodic Table symbol for copper is 'Cu');
- Another egg! = '0' again;
- As I was rhyming to St. Ive, I met a number = '5' (It rhymes);
- Bigger than a teaspoon = 'T' (Represents a tablespoon).
This means that our next clue will be found by putting these all together in order and navigating to https://imgur.com/a/0Zxu05T/...
How to solve this one? Note that there are four references here to:
Morse code ('morose', 'codes', 'dash' and 'dot'). After much overthinking I finally found a way for the 7 words to be translated into useful Morse code, whilst also extracting a single letter or number from each for the next imgur link string. The trick here is to interpret consonants as dots and vowels as dashes. This yields the following set of Morse code:
.--- / ... / -.-. / --.. / .--. / .- / --.
Also noticing that the words appear on two tiers, this means we should interpret those which are higher as upper-case, and the lower ones as lower-case. This yields:
j / s / c / Z / p / a / G
So let's go next to https://imgur.com/a/jscZpaG/ where hopefully we will receive the final answer (since this was billed as the 'Last one!')...
Gargh! The OP has been fiendish and planted one further clue for us to solve! This is what we have before us:
So what do we do with this now? How do we find the ultimate answer to this treasure hunt - what was it all for?
Notice that we have many sets of triplets, the first digit of which is always 10 or fewer. Notice further that if we are supposed to consider "the very first place I "talked" to you", this would be the original hand-written note on the main puzzle page - the note left by someone at the fair. Notice next that this note has 10 lines - it is not unreasonable to deduce that the letters of the final message have been encoded using line-word-letter triplets...
For example, the first letter of the final message is represented by (2,5,1), and if we look at line-2, word-5, letter-1, this represents 't', the first letter of 'to'. Repeating this process for each block of triplets reveals that each block represents a word in its own right:
to / this / Welcome
free / you'll / advance'r
the / A / maiden
treasure / Welcome / To / need / might
to / this / Welcome
Welcome / laptop / only
In other words, the answer to this treasure hunt - the whole point in it - is:
THE FUN HAD ALONG THE WAY!