As other have told you already 矢 (⿱𠂉大, arrow) and 失 (error, flaw, mistake) are not the same (for the arrow the 大-like part doesn’t cross the top horizontal bar; think of it as 𠂉 being the tip of the arrow (probably that is what was originally depicted).
Wanikani also names the 𠂉 element “gun”; I don’t like that name particularly, but as gun is a weapon, the same as an arrow, it may help you.
(The second kanji is different too, in “collecting arrows” 矢取 (やとり) the second kanji is ⿸耳又; while in “mistake” 失敗 (しっぱい) it is ⿰貝攵)
Well, I like, in those manga reading exercices, also try reading things that almost everybody just ignores: the writings in the landscape.
The machine at the rear has:
The last kanji is hidden by one of the bubles, but the 木 radical is visible,
so I supposed (rightly) it is 機 (machine)
食券 (しょっけん) : meal ticket
販売機 (はんばいき) : vending machine (販売=sales, selling)
Practice is actually a good thing, as it helps correct one’s errors.
At first I misread 券 (刀 (blade) radical) as 劵 (力 (power) radical),
but as 食劵 showed nothing on dictonaries I took a closer look and saw the difference.
And for 売, as I didn’t remember its On-reading, I searched it by components
on the components matrix at jisho.org … and was unable to find it…
Oh my! I had always written the upper part like this 土 (earth, bottom line larger),
but it instead like this one 士 (warrior, upper line larger)