basicall what I mean is, that when I use remote play, my internet is extremely slow on other device like when I download something
That doesn't necessarily answer the question.
There are two places bottlenecks can be occurring. Consider this:
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Think of your wireless router as an airport, the packets (how your computer moves data from it to the router) being sent back and forth as airplanes, and your actual data as people on the planes.
1. On your home network
An airport can only handle so many planes taking off and landing at any given time - it is only so big and the flight controllers so skilled. If more planes attempt to land at the airport than it can handle, some are going to end up crashing into one another. With all of the crashes, lots of planes and people will be lost, and even less planes than that will be able to land because it takes time to clean up after the crashes.
2. On your internet connection
No matter how many planes can land at your airport at any given time, the people have to be able to get off the planes and leave the airport before the next set of people can get on the plane. If there aren't enough cars or buses leaving and arriving at the airport (the connection from your ISP), it doesn't matter how many planes can land at or leave the airport - you will always be waiting on the people.
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My question is: what is slowing down your airport? Is it the number of planes it can handle, or the number of cars and buses?
Attempting to browse the web on your laptop via wireless will seem extremely slow no matter which of the two is. Attempt to do the same thing on a computer that has a wired connection to your router. If it is still slow, then it is your actual internet connection, if it is not, then it is your wireless router.
Once you figure out where the issue is actually occurring, it is easy to solve.