Veg stage? Ready for 1st topping?

You can easily cut off the main head already after the second internode after the first two round leaves but I would tell you to remove the two sundeck leaves on the head in order to get more light to the lower internode and then twist the main trunk in order to remove the apical dominance without slowing down due to the stress of the cut, then do as you want you can already cut if you want

Looks like she's still got her cotyledon, wow! She's a quick grower for sure. You're definitely in the clear to hit her with a topping. At this stage and health, she'll recover in ~3-5 days. Solid start, my friend! 😎

I myself like to top the fifth growing node.

Top your plants after they’ve developed between 3–5 nodes, as this is when their roots and stems are strong enough to recover from the stress of the process.