When I was first learning to drive my parents wouldn't let me do so unless I was driving a manual transmission, or stick shift vehicle. While it can be frustrating at first it can very easily become second nature and in turn is a very useful skill to have. It has been said that once you are able to maneuver a manual transmission correctly you can get behind the wheel of any existing motor vehicle. So few people are able to drive a manual these days, it is a skill that has gotten lost in translation and I can't imagine why. It will make you a better and more aware driver and like many skills all it takes is a little practice.
In order to learn this skill one must have a valid driver's license. For some drivers it this skill could be picked up in as quickly as a days practice, for others it may take a bit longer to figure out. But no worries, when broken down, the process is easy to understand and then all that is necessary is correct execution.
First, if you press the clutch, your engine's RPM will decrease to idle. The engine's pressure (to put it simply) powers the power steering and braking. Normally, the pressure of the engine idling will be enough to support the power braking well, but you might find braking easier when you let the car coast in fifth gear.
The dangerous part here is that your engine won't get forced to rev by the car but it will become possible that the engine stops during coasting with the clutch pressed. If it does, braking will become VERY hard. So don't make it a habit to coast with the clutch pressed.
Also, using your clutch and gas pedal to stay still when on an inclined road, will mean that the clutch plates are sliding over eachother and generating a lot of heat which means they will wear very fast. So USE THE HANDBRAKE when stopping on a hill.
A useful tip when having to slow down is to shift down and let the engine rev a little extra, thereby slowing you down. This will save brake pads. Trucks even use a valve in the exhaust to be able to slow down even more by partly blocking the exhaust.