Teensy 3.6 has two USB ports.
The Micro-B connector is a USB device port, which can connect to a USB host using
this Micro-B cable.
The 2nd USB port is 5 pads on the circuit board. They are meant to be used with a header (DIY soldering required) and
this USB host cable.
Both cables can be connected at the same time. However, if you do this, be aware the Teensy 3.6 and the whatever devices you plug into the host cable will be powered by the Micro-B cable. Normally this works fine, but if you have power hungry devices, it's possible to draw too much power or have other power-related issues when you hot-plug the USB devices.
Software-wise, both can work, if you craft your program to respond to both.
The main (Micro-B) USB port is configured by the setting in Tools > USB Type.
The 2nd USB port (host) is used with the USBHost_t36 library. The types of USB devices it supports depends on the list of object instances you put into your code. See that library's examples for details.
Both USB ports work independently and simultaneously. Data never automatically moves between them. If you want to "connect" something from one to the other, perhaps have the USB serial or USB MIDI which appears to your PC "connect" to a similar USB device plugged into the Teensy 3.6 host port, you would need to add code in loop() which responds to incoming messages from one or both sides and transmits whatever messages are appropriate to the other side.
How exactly you would do this depends on what you're trying to actually accomplish, which _still_ isn't clear, despite the many messages you've recently posted.
I really can't write any more to help, without a more specific question. But I would like to ask you to, please, refrain from reposting similar questions as many different threads on this forum. Please, help us to help you in the most time-efficient manner possible by keeping the number of threads to a minimum, and please please please try to be more specific about what you're really doing. We can help you better if we actually understand.