I’m currently in a similar situation to you as I’m looking to transfer to a different uni after completing my foundation year.
What I’ve done so far is:
Create a new UCAS application, add your 5 choices and under ‘Education’ add the current university you’re attending and select foundation year. Then fill that in (modules, current grades you’ve received etc.)
Email any universities you are considering and explain to them your situation and that you’d like to transfer. Don’t limit yourself to your 5 options! Email as many as you’d like because not all 5 of your options may accept foundation year students/ transfers or you may not be applicable for their course if say for instance, they primarily base admissions on A-level results.
You’ll need to provide them with your new UCAS ID, your course syllabus, your transcripts for your foundation year, your A-levels, your GCSE’s and your predicted marks for each module.
To get your syllabus, transcript or any predicted grades, email your course co-ordinator or in some instances it can be found on your student portal.
From what I’ve found so far, certain uni’s if not most accept foundation year students to then go onto to start their undergraduate as a first year. However, not every university can pre-asses you. I know Bristol does not pre-asses students and you have to apply anyways and wait and see if they accept you or not.
But some some DO pre-asses students and will let you know if you’re applicable or not.
They primarily base it on what you’re learning in your foundation year and if it meets their requirements. Once you’ve sent them your syllabus, they’ll examine it and let you know if you’re applicable/ or meet their requirements to start your degree with them.
From there, they’ll either let you know if you should apply to them through UCAS or may give you a contextual offer ie. If you get 75% in X module or 70% average once you’ve completed your foundation year we can offer you a place.
After you’ve completed your foundation year and receive your grade(s), you must then email the universities you’ve been in contact with and let them know how you’ve done as the results you receive from your foundation year don’t automatically get put on UCAS like A-levels do.
Hope this helps,