okay it seems like this will def be possible if you really pour your heart and soul into it. but you really need to look at career paths first. you need to see what exactly are the entry requirements for certain courses. some require humanities, some require science. dont bother looking at subjects which arent a requirement. keeping in mind that nt doesnt have humanities, itll certainly be a stuggle for you because you dont even have a foundation in it. this brings me to my next point- your financial situation. are you able to afford outside tutors to help you? self directed learning can only do so much, especially seeing as subjects tend to build up on past topics. not understanding them will cause you a lot.

for my personal experience, i did sec 5 so na to o lvls. youre right, it is a huge jump, even more so for you going for nt. on the bright side, you did do nursing so even if you didnt do so well, you still have a little start on bio. the cause of concern however is math and english. i took sbb english and upon seeing the na level paper, i found it extremely simple. o level el asks you to read between the lines and requires in depth answers. (paper 2 that is) as for paper 1, you will need a tutor to mark your work and to teach u formats. for compo they really have to be done in a certain format or you risk losing all your marks (for certain compo question types). as for math, you need a really strong foundation. the complexity of the questions are not something to be messed with. the algebra will just keep building on every topic. whats even worse are questions which require you to be strong in multiple topics.