If the caliper leaks brake fluid, the immediate problem isn't the brake pads - it's the brake lines (or the connections). Get that fixed pronto!
As long as it is DOT3 brake fluid you are fine.
Most likely the brake fluid will corrode and eat-away the seals on your power steering system. Brake fluid has a mineral in it that the rubber seals of the PS system can't handle. If you drive it long enough you'll either get severe leaks, or potentially the pump will seize. Best advice is to drain the system, fill with proper PS fluid, run it, then drain again. Get clear fluid if you can so you can tell when the brake fluid is out. This will likely take a few bottles
You top off brake fluid when the brakes are changed. If the brake fluid is low there is a reason. Get them checked out at that time. Most auto technicians will not top off brake fluid for this reason. The fluid lasts as long as the breaks.
The caliber needs replacing. Also I would suspect your brake system needs flushing. Replace all the old contaminated fluid with fresh brake fluid from an unopened can.
as long as the DOT rating of brake fluid is the same as the existing brake fluid, it will not matter what brand u use
The fluid level in a transmission will not change unless it leaks.
There is no specified time to replace the brake fluid of any vehicle, as long as you keep it topped up. Brake fluid does not 'wear out'. I have replaced the entire brake fluid on only a few occasions, and always only because I have been replacing seals or brake cylinders and it made sense to replace fluid then, before bleeding the system.
Brake fluid will make the surface of the tire slick, resulting in loss of traction. If left un attended for a long period of time, the brake fluid will "dry rot" the rubber and cause separation.
Master Cylinder low of brake fluid, grinding when the brakes are applied, and long brake pedal travel on a vehicle with brake shoes instead of brake pads.
The seals in a brake system will dissolve if they get any petroleum product on them. the system will not last long, and could fail at any time.
I recommend you use only genuine Honda Brake Fluid DOT3 but you can use another brand as long as it is DOT3.
the brake fluid reservoir is in the back of the engine on the driver side, you will need a thin and long funnel that it will reach the neck of the reservoir, carefully add fluid, allways checking the level.