In CMD you have to open the folder you created ie ADB-Fastboot
So type cd ADB-Fastboot , you are changing the directory to the one you created.
Then follow the other instructions.
Without being rude you do not seem to have sufficient knowledge to dabble with you phone....
Once you get it going I would not play with it till you have read a bit more and watched a few videos to bulk up the level of competency,
I don't have much knowledge at all and you can bet, I won't be messing with it again
We're nearly there, what do I do?