You can give up if you want to-- but remember that your GCSEs impact your A levels, which impact which university you go to (take it from a current year 13 student lol).
You don't want to be the only person unhappy on results day, realising that you could've tried but didn't bother.
So, here are things you might want to do:
Two months is a tight amount of time, but you can definitely achieve higher grades if you start focusing TODAY.
Step 1: Become more structured: use a timetable and allocate short bursts of revision in each subject (plz try to follow this it makes life so much easier)
Step 2: Firstly identify the topics you are the worst at in each subject using RAG sheets (you can likely find these sheets online --> or ask your teacher)
Step 3: What has been your most effective method of revision? If you haven't yet identified this, you must do so now, or you will procrastinate on your work
Step 4: Use this method of revision, and after being secure on the knowledge, do past paper questions. For essay subjects, just do essay plans. Whilst you do these short answer questions/ essay plans, if you realise you don't remember something that would help you understand the question, revisit the topic through your class notes, youtube videos, your teacher etc.