How to be a commercial pilot?

Hi, i am in Yr 10 and getting prepared for my GCSE's

i just wanted to know whether a person can be a pilot who is doing BTEC. Apparently, I am doing only 3 GCSE's and i am quite confused with that because we all need 5 GCSE's?! I will check on that.
The subjects i am doing at currently:
BTEC:

Engineering
Sport
Science
I.C.T

GCSE's:

English
Maths
RE
As i am coming to my conclusion, please could you tell me on whatsubjects do I need most focus on and what grades do i need!

Read more: How to be a commercial pilot?