does that mean like a protocol which i will program myself?
or a premade, lower-level one? and if so could you recommend me of one? or just give me a direction..
A protocol is a set of defined signals over a line. Between the PC and Arduino you could use a serial line (USB cable) as the carrier.
The defined signals can be a string like <servo 1 20> which could mean that servo 1 goes to position 20. Because Servo is such a long word you may abbreviate it to <S 1 20> . The Arduino can signal back or just
Note that I write the strings in <>. These are added to the commands to let the arduino know that all character of a command are received or that a new command is beginning.
There are many examples on this forum for similar protocols. There is also a message library that may be very useful for you.