Its not particularly clear from your video what your problem was as you appeared to have great difficulty getting stable repeatable readings when probing round your breadboards. Also for %DEITY%'s sake, SAY WHAT YOU ARE DOING, what readings are, etc. If English isn't your first language and you are unhappy with your spoken English, you may prefer to subtitle your videos, or for readings, edit in a closeup of the DMM display, overlaid in the corner etc.
You either need good quality croc-clip adapters for your probes to go onto component leads, or short adapter leads terminated in gold plated Dupont pins or similar, or best yet, good quality 4mm banana plug to Dupont pin leads, which avoids the extra contact resistance problem of adapters. Although probing around is the most convenient for quickly locating a problem area, when you want to take a reading to share with others or for your lab notebook, to get stable results, take it hands off - i.e. connect the leads then take the reading without touching the circuit.
There are a few breadboard traps for the unwary (apart from their generally poor performance at higher frequencies due to inter-strip capacitance and lead inductance):
Some long breadboards have split bus rails, and if you want end to end continuity, you have to install a jumper over the gap in the middle. This is usually indicated with red and black or blue lines along the bus rails with a gap in the middle where the split in the rail is, but some breadboards may have split rails with no or continuous rail markings so always check a new breadboard with a multimeter!
Cheap & nasty breadboards are generally problematic, mostly due to poor quality contacts, that often require grossly excessive initial insertion force, then distort and fail to hold reasonable contact tension, or even block the hole. The contacts are made of mystery metal - often mild steel 'flash' plated with low grade brass, nickel or tin, so are very vulnerable to corrosion if the board is exposed to atmospheric or other contamination + high humidity.
Perhaps the most irritating fault is if the bus strips aren't made with a single un-cut strip of contact groups, but instead are two or more strips with a butt-joint between them, that typically goes high resistance.
Using a breadboard for more than 50V, 500mA is insane, and in practice, its better not to exceed a few hundred mA through *ANY* breadboard contact, even good quality ones. Also if you don't want to melt the plastic shell, don't exceed 1/3 of the wattage for any resistor, 1/2 W for any un-heatsinked TO-220 package, and derate the power rating of other semiconductors by at least 50%!
Cheap Dupont pin jumper wires are *EVIL* - use 24AWG solid hookup wire, cut to the actual length required.
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