Depending on what funk you're playing, it can be a weird. Also tempo changes in the tracks can make it more difficult.
If you want to count the BPM of your tracks you can get this app https://itunes.apple.com/au/app/bpm/id296956954?mt=8
Find a few records you have that are similar tempo, or even the same tempo would be perfect for beginning to learn. Something with a consistent kick makes it easier to get the technique down pat in the early phases.
This youtube playlist is full of beginner DJ tutorials, scroll down to the bottom (hit load more) to find some of the older ones which are based on vinyl.
https://www.youtube.com/playlist?list=PLkqsu4WzeMg7hmBi9Nr7lK4lqoOYZpVvW
Also just to touch on what oxy said: -2 on the pitch fader isn't equal to 2 BPM, it's -2%. If the track's original tempo was exactly 100 BPM this would be correct, but if a track was originally playing at (exactly) 80 BPM, moving the pitch fader -2% would make it 78.4 BPM. If a track was originally at 130BPM, -2% would make it 127.4 BPM... Also one of the joys of vinyl is you need to be aware of the fact you may get small fluctuations in pitch depending on how good your decks are etc.
Good luck