Any english teachers who are foreigners in Japan
This is my field, so read carefully. I have information and questions for you.
When do you want to teach here?
Does your college degree in building construction have "bachelor's degree" on it? Is it from a vocational/technical school or a 3-year college or a 4-year university?
As Mike Cash has alluded to already, your written English skills are not stellar. Even though this is a discussion forum, and people often consider them not worthy of writing well, I'd suggest that you write better so we can truly assess your ability. Otherwise, I'd say at this point, nobody is ever going to hire you except some shady outfit.
As for
I do really want to teach, I like helping others excel at things and I like seeing progress and just over all being a good supportive role to people who need assistance
you should do some research on what English education here is like. Most students don't really want to "excel". English is forced on them at younger and younger ages, and despite parents' concerns for their children's career, schools don't really help much, and many university educators don't know what English is needed in many jobs for their students.
At your age, you are extremely minimally qualified right now to teach with a working holiday visa, but you are very young to be in a teaching role, and the market here is overly saturated with people far older than you (and many with experience here). So, your competition is really high, even though a WHV means an employer doesn't have to be your visa guarantor. Also, WHV holders get taxed 20%. You don't need a degree to get the WHV, but many employers may insist on the degree regardless.
Entry level teaching jobs are eikaiwa or ALT (the latter requires a degree, not WHV). ALTs get hired directly from dispatch agency or the JET Programme. Most eikaiwas don't hire from abroad, so you'd have to be here first. Even the ones that recruit in Canada require that you pay expenses to attend their 1-3 days of hiring at whatever limited locations they have. Eikaiwas typically work from noon to 9pm any day of the week; ALTs work from 9 to 5 in public schools Monday to Friday.
You can teach on the WHV, a work visa (if an employer sponsors you for it, and a college degree is needed in any field), a student visa (part-time work only, and you could attend college or a language school, but you have to show that you can pay all tuition up front), or a cultural activities visa (part-time only, but you have to show previous experience in that cultural activity plus find a master in it here to continue your studies). You're probably not in a position to get a spousal visa (married to a Japanese) or a dependent visa (married to a fellow foreigner who has a work or student visa), but both of them also allow work.
Work contracts are typically for a year, so don't plan on getting something for just a few months.
I'm not pursuing a career in teaching English in Japan, just wanted information on it
Why? As I asked above, when do you want to be here? The way you write, it sometimes sounds like you are trying to plan for something, but it isn't clear what that is. It also sounds sometimes like you are only looking for a foot in the door for some uncertain purpose unrelated to a career.
Or if not english teaching, would there be any jobs foreigners can get into abroad for a year in Japan?
Not without a college degree, except for places that might want to accept you on the WHV, but at your age that's unrealistic. You're going to need the degree, some related work experience (demonstrating skills that are needed here and often not already had by locals), and most often with pretty high level of Japanese language ability. You might want to consider an internship visa.
