F7 knowledge is essential to give yourself the maximum possible chance of passing P2. You need to ensure that you are happy firstly with group accounts, so I’d recommend that you look at some of the recent past exam papers and attempt the group accounts questions.
Once you’re happy with that then you need to get familiar with the accounting standards examined in F7. I’d recommend that you look at the examinable documents list on the ACCA website to get familiar with the ones that are assumed knowledge at P2 level.