Can I reapply to the same uni course next year if I get rejected this year?

Say I apply to a course at a university and they interview me and give me a conditional offer, but I fail to meet the conditions and am rejected. Then I decide I don't want to go to university yet, instead I'll work at trying to improve my qualifications/grades this year. Can I still apply to the same course at the same university the next year?

Bonus: I applied to UCL but now realise I probably won't make the grades for the condition. I want to take a-levels and reapply next year with - hopefully - better grades. However, I want to also take a 2 year part time evening course at UCL this year instead of doing the under graduate. Is it weird if I'm rejected or pull out of the offer then apply for a lower level evening course, then I apply via UCAS to the same course at the same uni I got rejected from? What would admissions think? Is it acceptable?

Just realised I've needlessly phrased one question in multiple ways.

Say I apply to a course at a university and they interview me and give me a conditional offer, but I fail to meet the conditions and am rejected. Then I decide I don't want to go to university yet, instead I'll work at trying to improve my qualifications/grades this year. Can I still apply to the same course at the same university the next year?

Bonus: I applied to UCL but now realise I probably won't make the grades for the condition. I want to take a-levels and reapply next year with - hopefully - better grades. However, I want to also take a 2 year part time evening course at UCL this year instead of doing the under graduate. Is it weird if I'm rejected or pull out of the offer then apply for a lower level evening course, then I apply via UCAS to the same course at the same uni I got rejected from? What would admissions think? Is it acceptable?

Just realised I've needlessly phrased one question in multiple ways.

You're not guaranteed to get an offer, so you should have other options as well. They might not accept resits, or they might accept them but only if there are no other "better" applicants. You have shown that you cannot get the required grades the first time round, and that even a uni offer won't motivate you to succeed. You also need to remember that generally, applicants get better each year and entry requirements increase. So you might look good this year, but if standards increase you might not be.

I have other options. I'm not resitting, I would be taking a different course. It would probably look bad if my name appears again during applications for the same course next year? Is anything wrong with doing that though?

No, it shows a sustained interest in the course, just add to your personal statement within that time frame in order to show them that you are working hard to get onto the course.