Welding for the first time - need advice

Once you get your welder settings correct, try welding on some spare metal first until you get the hang of it.

Watch your weld bead. The bead can indicate to you if you are going too fast, or slow, or just right. The bead should be nicely curved. It should not be elongated. If it is elongated, you are going too fast. If the bead is bunching up, it is too slow. If it is nice and curved, then you are going just right.

Get some pictures of a good weld, then use that as your target weld. Keep practicing until you can match that.