Hi - I am growing a mango tree from seed, but the plant is growing thin like a weed and not like a tree. I planted it on January 28. See the pic

That really does not look like any Mango that I've ever grown.
Did the stone germinate and you transplanted it into this pot or did you sow the stone into this pot ungerminated? My guess is that what you have is a stray seed in the compost that has germinated.

The roots germinated in paper towel and then I moved it to the container in the pic. I will unearth it and see where the "weed" is coming from.

Hi there Qmedic 😀
It's going to need as much direct sunlite as possible, but gradually.

Also let top 1 to 2 inches of soil dry before watering. 👍
😎😎😎