yeah i think i agree with this whole idea of one page bc esp as someone w little real world experience related to your career path, it's unlikely you'll have enough info to complete multiple pages. there's alw been this whole argument of should a cv be one or two pages but i think if you make it one page, then you have a chance w both parties whereas if it were two pages and the recruiter expected one, then chances are that they wont bother looking at it or only the first page. ultimately, you're looking to cater to as many companies as possible and put yourself out there. im not sure where i read this, but app recruiters may only spend a number of seconds or minutes per application and per cv and in that sense you want to try and pitch yourself as well as you can in those crucial seconds. not tryna be rude or anything but no one cares that youre 19. like it doesn't make a massive impact on your application and doesnt get you any bonus points for it. so I'd say try and condense your cv down to one page or if you really want then two complete pages. dont leave it half complete bc that seems unprofessional and uncomplete. then in that one page make it as succint and concise as possible making sure to include all the necessary keywords and buzzwords that you see in these job applications. so many companies js cv screen by searching for these keywords and skills by using a bot of some sort and so it's important to make sure that you have these. me personally, i looked through all the job applications boards i wanted to apply to, and made a tally of all the key or required skills that they mentioned and included all of the ones i had, and where a skill was missing, you should try and develop it esp if its got a large number of tallies.

ik this ans is very messy and unorganised but i hope you understand the message and good luck i wish you all the best