A Levels / gcse trauma

Hi everyone,
I am an international student in the United Kingdom, I am currently meant to be in college as I will be 18 this September. I applied to colleges and the first college offered me T levels assisting adult nursing, the second college offered me combined or triple science while the third college offered me chemistry, physics and English language.
My first question is that I need to know the difference between combined and triple science and also if medical schools accept any of them .
Secondly I need to know which college to choose bearing in mind that I achieved this grades in my waec (math B3,chemistry B3,English language C4,physics B3 and biology C6).
Finally I need to know if I should consider reseating for gcse in my sciences to achieve better grades .
Thank you in advance for your help and assistance in choosing a college that best suits me for medicine

I need to know the difference between combined and triple science and also if medical schools accept any of them
As far as I know, you would require A Levels or IB (if you're doing qualifications from England) to go into medicine at a UK university. T Levels and BTECs are generally not accepted.

In terms of subjects, they are also very specific: biology and chemistry at certain grades (grades will vary from uni to uni, but generally A or A* for A Levels).
If you only have an A Level in Chemistry, you're limiting yourself to 19 of universities to do medicine from (see: https://www.themedicportal.com/application-guide/choosing-a-medical-school/what-a-levels-do-you-need-to-be-a-doctor/).

As far as I know, there are no combined or triple science in A Level or IB as single subjects. If you want to check for the specific university (there are 33 in the UK that offer medicine), do this as soon as you can.

I need to know which college to choose bearing in mind that I achieved this grades in my waec
The international conversion for college applications is terrible; you would need to check with the individual college.

I need to know if I should consider reseating for gcse in my sciences to achieve better grades
As far as I know, GCSEs are used to gauge how high your A Level grades will be (personally, I think it's a bad way to go about it, but it's how universities go about it). If your grades are not specifically affecting your application for college courses or university courses, then I don't see much point in resitting.
Should you resit, you should also be aware of whether the individual university accept resits. Resits for GCSEs are relatively minor and makes little difference in your application, but resits for A Levels is rather big for them.