IGCSE Physics is the physics exam of the pre sixth form stage and its depth is limited. What troubles students is not the topics but the exam's own way of wanting answers.
Core and Extended
There are two tiers. Core covers a narrower syllabus and caps the highest attainable grade. Extended covers the full syllabus and is open to the top grades.
Where physics will continue at A Level or in the IB, Extended is required. That decision is made early and with the school, because later transfer is limited.
Scope
Motion and forces, work and energy, thermal physics, waves, electricity and magnetism, the basics of atomic physics, and space.
The topic list overlaps broadly with the curriculum in Turkey. The difference is that the same topics are taught in English terminology and with less mathematics.
The practical component
A separate paper is built on experiments and measurement. In schools with laboratories it is taken practically, elsewhere in a written form that asks the student to read and interpret an experimental setup.
For external candidates this paper is usually the weakest link, because a student who has never done laboratory work does not recognise measurement error, repeat counts and control variables on paper.
The form of the answers
The mark scheme looks for particular phrasings. When explaining an event, which quantity increases and which changes as a result must be written in order. A correct fact written in the wrong order does not earn full marks.
This cannot be learned without reading past mark schemes, and it forms the last part of preparation.
The formula situation
Some formulae are provided in the exam and some must be memorised. Which fall into which category is stated in the syllabus document.
A student who does not draw up that list may memorise the formulae that would have been given and miss the ones that need memorising.