You didn't say what chassis you MH sits on.
However whining noise when turning the steering wheel and when you step on the brake probably indicates an issue with the power steering pump. It provides assist for both the steering and brakes for many motorhomes of the vintage of yours.
It might just be low on fluid or maybe just getting tired.
2003 34' Georgetown on W20 Workhorse Chassis. UltraRV power mods. Front Sumo Springs, Rear P32 Sumo Springs, UltraRV Track Bar.
1998 Jeep Toad.