welder/welding

You should not be using straight argon. Normally you use an argon/ CO2 mix. I don't do much if any really light sheet metal. I use straight CO2, the same stuff that is used for a cok/ pepsi machine. It is cheap and liquid in the bottle, and lasts a long time. CO2 allegedly gives you somewhat better penetration, but with somewhat more spatter.

If in doubt, crank up the gas pressure. RECHECK the book and MAKE CERTAIN you have the torch wired (where the torch meets the box) for the correct polarity.

As said earlier, there is ZERO chance flux core will help your welding.

Are you sure of the wire size, do you have a good tip (don't know if this is a used/ new machine) and is the tip the right size for the wire? I assume you are using the chart supplied for settings for a starting point. I have the older 180 Mig, not a "pro" and the chart is usually pretty darn close.

Also if there is a question as to gas flow, buy an inexpensive flow gauge, and do research to get the right range/ right one. These are a little tool you hold by hand on the end of the gun, turn the wire speed to 0, and trigger the thing and read the flow

Here is one example, not necessarily recommending this one or not

Amazon product ASIN B06XW8H8W1