24 or 26 AWG cable for my arduino UNO ??

invader7:
Thanks for the info , what about the cable ? 26 AWG is very thin and unstable for a breadboard ?

Only if it's multi-strand, not solid core.

invader7:
Do you recommend buying a 24 AWG or 22 AWG instead ?

I recommend spending $2 on some proper breadboard wires with pins on the ends.