BTEC Level 2 Certificate equivalent

I heard that BTEC L2’s can be equal to more than 1 GCSE atleast when applying to a sixth form, is that true of all L2’s or just Extended Certificate/Diploma? if it helps the exact course I want to do is BTEC Level 2 Certificate ICT Systems & Principles

A BTEC Level 2 Certificate in ICT Systems and Principles is the equivalent of a single GCSE. If that's all you really wanted to know, then you can ignore the waffle below.
What you have heard is correct - BTECs come in different sizes, and can therefore be worth more than one GCSE. Unfortunately, there's not a desperately straightforward way of mapping one to the other.
The "size" of a qualification is based upon how much time it takes to teach / learn it. There are two measures:
• Guided Learning Hours, or GLH, which is how much time is how long it would take to teach the average student the content.
• Total Qualification Time, or TQT, is GLH plus the self-study time which the average student is expected to require to complete the course.
A GCSE is designed to have a TQT of 120 (so two GCSEs would have a combined TQT of 240). GCSEs aren't expected to require self-study, so they also have a GLH of 120. For BTECs, GLH and TQT will be different, as self-study is expected.
If two different qualifications have approximately the same TQT, then they're approximately the same size. The course you mention, a BTEC Level 2 Certificate in ICT Systems and Principles, has a TQT of 130. (We can see that on the Pearson web site, here.) So it's slightly larger than a GCSE, but I'd expect it to be treated as being equivalent to just one anyway.
The word "certificate" in its title just means a TQT of more than 120 but less than 370, and at level 3 the term "certificate" tends to be used for a BTEC with a TQT of 180 and the term "extended certificate" for a BTEC with a TQT of 360. So an uninformed sixth form might assume from the word "certificate" in the title that your BTEC has a TQT of 180 and is therefore worth 1.5 GCSEs. But I expect most won't make that mistake.

Thanks so much! Your explanation is much clearer than anything I found online 😅