How to learn welding technology well?

I bought a DC welder from the Internet. When I started welding, I used the current according to the current instructions on covered electrode's package. When welding a T-joint, you can't weld it under any circumstances. I also went to Baidu to search for welding videos and watched the research repeatedly. In a word, I just can't weld them. After welding, the iron sticks to both sides and doesn't melt together at all, but dare not turn on the big current.

After a period of time, I found that the greater the current, the higher the probability of welding, so I understood that my previous welding current was too small and should be increased.

After increasing the current, it is found that sometimes the welding is not good and it is directional.

After such feelings, I found that the current is not good, it is easy to burn the edge, and it is not beautiful. Then I really found that the method of transporting strips is also very important.

Now five packages of coated covered electrode have been welded, and it feels a little.

If there is more welding, it will be fine naturally.