If you want, you can skip ahead and complete the skills and drills badges without using minecraft and test them in the simulator (within the browser). However, keep in mind that the simulator can't at the moment render creatures or lightning. That said, you don't need to test the mod in order for to unlock or 'win' the badge. The badges will always unlock when the answer is correct, such as when the mod matches the mod in the screenshot badge instructions (posted below the badge video) .
To unlock the write your first mod badge, you should place a purple function block, click the title and type main (lowercase). Then inside the function block, it should say Hello, World! just like in the badge instructions, capitalized and punctuated just like that.
In the run your first mod badge, click the orange'load starter code button on the badge instructions -- that will bring up the code you wrote in the previous badge. Then scroll down the badge instructions and select the correct quiz answer. After that badge, I recommend doing the skills and drills < learning to program badges. There about 100+ badges in that category