Hello guys,
I am not so experienced in USB connections and protocols. What I would like to know is how to build a USB host for my arduino Uno( which is made on a breadboard) so I can connect it with a USB cable to a PC? I use an ATMEGA328p. What other things should I must be aware of?
An USB host is something else.
Use a usb-to-ttl-serial adapter. If you buy one with the DTR signal, you can use that to reset the avr chip to automatically upload the sketch without the need to press the reset button.
Most of the time a FTDI chip or PL2303 is used for the usb-to-ttl-serial adapter.