If I understand the ask, you’re rebating the threshold to go over the LVT. That’s quite fiddly to do freehand with a router. You can do that sort of stuff with a router table but it might be more accessible to use a track saw (or a circular saw against a straight edge). To do that safely, you tape the threshold onto a wider bit of material of the same thickness and that gives you a nice steady surface and no tipping.
You could use a palm router with a guide but the same thing applies. Attach the threshold to a wider piece so your fingers aren’t anywhere near it. Router accidents happen fast. The guides never seem to be that clever so a straight edge to work against can be easier than a guide.
Also, make sure you understand about pushing the router into the cut and avoiding a climb cut (again, if you want to keep your fingers).
Don’t wear long sleeves with any dangly bits. Don’t wear gloves. Don’t wear a hoodie with dangly cords. etc.
[/Granny egg-sucking lecture]