"SCQF Level 7"
Scottish undergraduate degrees, and their relationship to secondary school teaching, are different from what's found in England and Wales. A typical four-year degree course will feature students taking a variety of subjects in their first year, narrowing down to advanced study in just one or two by their final year. Scottish students, having taken Highers and maybe Advanced Highers, will have a broader base of subjects than their English counterparts; they will not have done as much mathematics as someone taking English A-levels and going on to an English maths degree. They skew younger than in England because it's possible to enter with only one year of Highers, compared to two years of A-levels. People with A-levels and other qualifications do enter the Scottish university system, and might start at the second-year level if they prefer and if their grades permit.
Accordingly, the first-year mathematics teaching would usually be designed to take in a student population who are not all expecting to continue with mathematics, and who have a diverse background in the level and topics of what they have done so far. The teaching would be trying to set them up for their next years of study, either in mathematics or in some other subject such as physics where people typically opt for first-year maths as well.
"SCQF Level 7" is a slightly technocratic frame for this. Formally, it corresponds to RQF level 4 and EQF level 5, and is associated to the CertHE level of qualification. But somebody taking these courses at a university is not necessarily headed for a CertHE in Mathematics, if only because a first-year Scottish mathematics course might only represent 25% of the total credits taken that year. It's more like what the English universities sometimes call "foundation year" (an optional one year of transitional study before the regular undergraduate degree), or the "short cycle" of the Bologna process. It's not a full course of study leading to a freestanding qualification. These level numbers are back-formed from the practice of what Scottish universities have been doing for a long time, so it's probably easier to understand that than to try to understand the SCQF abstraction.
Characterising this as "high school level" is neither right nor wrong in global terms. It depends on the school in question: the Scottish education system draws the line in a different place from the English one. For a Scottish high school, students will have seen some of this (assuming they've taken Higher maths), or even more (if they've taken other more advanced qualifications while at school), but not always the same subset, and the university-level presentation will be different. So in the Scottish context, it's reductive and inaccurate to say "high school level", as that does not reflect the structural purpose of the teaching.
"My contribution to (university name)"
I agree it's hard to interpret what's wanted here, and it's only a five-minute slot. It could be a totally generic opportunity to make the case for your fit to the role, or it could be asking about what you bring to the university other than performing assigned teaching duties within the department. I think that the thing to do is look back to the job description, which should include a numeric grade and a long list of desired characteristics. The grade will match up to nationally-standard criteria, which are the product of lengthy negotiation between universities and unions about the reasonable scope of duties for a "lecturer", "senior lecturer", etc. There should be some sort of hint in the job description, or in the institution's standard language for that level of job (which you could find in the section of their website dealing with promotions), about the kinds of things they would like to see. For example, Aberdeen's recently-revised criteria, to take a non-Glasgow example, cover a wide variety of possibilities and say what evidence they would consider indicative.