I had always thought the BX70 series always came with loader valves standard, so it would be unusual to not have them. You say you're new to tractors, so not wanting to be rude....but are you sure? Is there a loader stick? No hydraulic connections with blue/yellow/white/red caps on them on the right hand side of the machine near the engine?
If you don't have the loader valves, you can buy and add them, but as others have said, you're better selling what you have to someone who doesn't want a loader, and buying one with a loader already on it.
I added a loader to my BX2350, which did already have the valves. Even so I think I lost money on it, I would have been better swapping the machine for one with a loader. I think the underlying problem is that a 5 year old tractor with a brand new loader on it is still a 5 year old tractor - the loader basically becomes as old as the tractor as soon as you attach it. In my case, it cost me $10K to put the loader on (plus a couple of other fixups), but the difference in price between my machine and one with a loader already on it was probably more like $5K. In my country they're hard to get your hands on though, so I may have waited forever, I didn't think too hard about it and just bought one.