This is a incredibly complex subject. But a short explanation goes like this.
All profiles need to be done for the individual machines separately. So profiles you download form hardware vendors are not accurate, they are better than nothing but usually not much.
Reason for this is that the calibration and profile of a device will change during its lifetime. For example each monitor is unique when coming out of the production line and each print cartridge is different in combination with age its been stored and how much of it is used.
That means you need a colorimeter* that can profile your devices. If you do not have one then you can not even begin to play this game.
If you download a profile from a commercial printers site then you can assume that its quite accurate because they have a vested interest in keeping up to date profiles available and usually have some leeway to keep their stuff calibrated the same anyway.
Can I use them to print on my own home printer, to get an estimate of what it will looks like?
First things first
You need to be able to simulate the printer you have. If you have a colorimeter that can measure your home printers output then yeah sure you can estimate the print on your monitor**. This is relatively straight forward in most cases. Get the colorimeter out print a test sheet and measure. Than save and use that profile.
Simulating the commercial printer
Its even possible to make the home printer simulate the a press. It certainly has the potential to come closer than your monitor in some cases. Its also possible to have a software rip that simulates the raster pattern of the printer for a even closer hard proof. But this is considerably harder.
However, and this is important. It requires you to look at the print in a good light condition, preferably with full spectrum lights. Otherwise the different spectral peaks of your ink may in fact distort in way that the other print does not. This can lead to wildly different feel. ***
Still all is not as easy, see profiles deal with what happens to colors you can not repeat too. So its easy to fool oneself into thinking what you see is what you get. Sometimes it is sometimes its not. Even with gamut warning its hard to know.
So while its possible to do this with profile to profile conversions, which might work about right. In general, its better to get a software rip engine that can do this for you. But those are usually expensive or require quite much technical expertise. Also not every home printer is possible to use for this purpose. This requires a printer with something that can be controlled to a level that can be used by the rip. Usually this means you need to have a printer that understands say postScript or some other language (and usually can not be cheap direct windows print devices).
But if your not willing to sink a at least 300$-1000$ of money and several weeks if not months of time**** into this then, its not worth it. Note that this is not just a one time investment you need to keep doing this over and over again.
* You should also periodically calibrate your colorimeter... but nobody does that.
** Not all colorimeters can do this, due to software and hardware limitations. Usually to get your purse to become lighter.
*** Home remoldeling needed?
**** And this assumes your technically literate (its literally easier to build your own compiler)