This usage of too is an example of understatement. It occurs only with verbs in the negative.
My mother wasn't too pleased about the mess in the kitchen.
Variants with the same meaning are to be "none too pleased" and not to be "any too pleased."
It refers to a song sung by Pooh elsewhere in the story - see winniethepooh_uk.tripod.com/poohbear/id14.htm (scroll down a couple of paragraphs).
I'm pretty sure the sense is "I don't get any fatter no matter what I do", or "...whatever I do". It is shortened to "what I do" to fit the rhythm of the song.
"Too" in this sentence is being used as "very". This is one of the meanings that "too" can have in a sentence, functioning as an adverb. In this sentence, it is clear that the subject of the sentence is not very appreciative of the car - the sentence is also correct without "too", but a little less idiomatic.
After correcting minor syntax errors, the meaning OP intends is something like...
Now, let's use the formula above so that [+we can] achieve the further results
...but he wants to express this in a "fancier" (more formal) way. In which context it's worth noting that "imperative" let's is a relatively informal construction in the above.
Not "would become old."
"Become old" is OK, though you might mean "became old." The choice of tense depends on when all of this takes place. If the boy is young George Washington, so his parents are now long since dead, you'd use became. But if the boy is alive today and his parents are still young, then it's become.
By the way, in answering that, I ...
Neither of the answers is idiomatic.
Native English speakers do not talk about people becoming old.
They will say things like when they age, when they are old, in their old age, when they retire and so on.
If you have to choose between the two options, prefer when they become old but be aware that it is not fluent English.
When they would become old ...
The only grammatical fault with I can see with what you wrote is that you pluralised "birthdays". Aside from being uncommon to do so, if you were actually wishing that all future birthdays are happy it becomes a redundancy to then say "any many more". The other unusual thing about your statement is that you are wishing future ones be "happier", and that ...
My is not an abbreviation for "am I".
In Old English "My" and "Mine" were the same word, (min) But by 1200 a reduced form "mi" later "my" was used when the next word started with a consonant. And by 1500 "my" was used for all words. It is completely unrelated to "am I", which in Old English would have been "eom ic"
In some dialects, "am I" can be ...
Yes, it is wrong.
Have needs to be replaced by had.
The usual construction would be a hypothetical statement, such as:
Had that been shown, we would have seen it.
Alternatively, someone might say:
I will not have that being shown in my house.
Note that the verb needs to change from been shown to being shown.
To avoid unclear word combinations like '(their system) which I struggled with' or 'struggled with myself', I'd suggest to attach (or to write as a separate sentence) the words in this order:
... and, on occasion, I honestly struggled with that myself.
A conditional sentence can use the future tense in the second clause:
If you study hard, you will pass the exam.
If I have time, I will visit him.
This is called by teachers, a conditional sentence, type 1 used for future, real situations or facts.
Teachers usually teach present unreal or future conditionals as given in the OP's examples:
If you didn'...