Hey there

Don't worry if you are weak in maths it does't mean you can't take BCA. See during BCA you will have to do Coding in various languages like java, c, c++ etc. Maths of 12th level is required in BCA so you should start solving maths from RS aggrawal and RD sharma of class 11 and 12 to get basics and then move to higher level maths. Start from basic books it will be easy then use youtube lectures wherever required.

good luck