He shouldn't need to ask for help, it should be there for him. From both school and you.
Lots of children, and it seems to be more boys, don't read for pleasure and find it boring.
Does he read things that are not books? Comics? Cereal packets? Anything?
A frien's son wanted a lizard (sorry can't remember the type) and asked for money for presents to put towards the lizard, vivarium etc etc.
Mum said he needed to know how to look after ,so he had to use his money to buy a book and learn the right temperature, food, enviroment etc.
Your ds doesn't have a need to read, so he won't. Is there anything he wants that he would have to research? A pet or a trip somewhere? That would give him a reason.
Do not, whatever you do compare your ds1 to ds2.
Praise the things he does do, and do well. Maybe he is great brother, or does the washing up, or is a fantastic artist.
Everyone is good at something. Find out what ds1 is good at and encourage it.