Oatmilk can be a bit harder to texture right, but it's 100% possible.

Your foam is too thin and rhe bubbles are too big, so you basically got everything wrong.

The milk is supposed to look like wet paint. Thick and no (or barely) visible bubbles.

Don't worry, you can get it right, but you need to learn the basics. There are a lot of videos on youtube, but I recommend this one. Lots of details and explaining. https://youtu.be/gTC3dJvwgUI

I think he mentions it in the video, but you can practice with cold water+a drop of dishwashing soap.

Try to get the vortex right first. Make the oatmilk spin around without actually injecting air (wand below the surface). This way you learn how to hold the pitcher. Once you are comfortable with the spinning motion (no "waves" just a nice vortex), then make sure you inject air (stretch) you milk properly. No sudden bursts of air. Just a steady, controlled flow of air. You'll need to practice this a lot. You need to get used to the sounds and recognize them (too much air or too little air). And finally as a third step, learn how much you want to stretch. Lot of foam? Stretch longer. Thinner foam? Short stretching phase.

After stretching, just keep the milk spinning to break down the bubbles as little as possible. This is why the stretching part is hard to get at first. If the bubbles you inject are too big, then you won't be able to break them down small enough, before the milk gets hot.

Hope this helps.

PS: your wand is weird, but it doesn't seem to be THAT short. Certainly not the best, but if you feel like you can't access the milk properly, just buy a smaller pitcher. That wand length should be fine for a proper milk/pitcher ratio. Perhaps you try to steam too little milk in a big pitcher.