The screen in the end of the spout is probably clogged.
Clean the screen in the end of the spout.
No
Kitchen faucet? If so, the sprayer attaches to the underside of the faucet in the middle.
You cannot do this without a way of stopping the water. The sink sprayer is hooked up through your kitchen faucet for a reason. When the faucet is shut off, no water can come through the sprayer. If you hook up the sprayer to a water filter, the handle on the sprayer cannot handle the pressure of the water system and will continually run when the handle packs it in, more than likely when you are not home!
No, if the current faucet doesn't have a sprayer, there is no place on the faucet to attach the sprayer. It would attach on the underneath side of the faucet in the center.
If there is no air, then you cannot adjust pressure.
If the sprayer is working correctly, all pressure should be released by operating the wand valve while not operating the pump lever. (I'm assuming it is a hand-operated sprayer, not the kind with a powered pump.)
Try eBay.
Please be more specific about what kind of 'power sprayer'. - Are you referring to a 'pressure washer' ?
Many stores sell them. Definitely HD.
A pressure garden sprayer works by storing compressed air inside of a pressure vessel which usually is a plastic or metal canister, and allowing the contents of the container to be directed out through a wand or some other sort of pressure releasing device.
Yes, just lower the pressure considerably.