Re: which, where, in which
The part I have marked in red doesn't make sense at the moment. I will take a guess at what is meant:
Originally Posted by KSSEEJ
On the other hand, for/regarding the sports centres whose demands are slightly higher, the government could increase their capacity by upgrading their facilities.
Is that close to what you meant? I have assumed that the demands are demands for more seats.
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.