What your command is trying to do is replace the nearest player whose player name is tnt's mainhand slot. Because your Minecraft username isn't tnt, it is not finding you.
Unfortunately, it isn't possible to detect an item in a specific item slot in Minecraft Bedrock. You can, however, run /clear @p tnt -1 1 to clear a TNT from a player, and test whether it ...
There are two ways you could do this. The first is to just summon the entity at the correct place, as everyone else has been telling you (I will use a sheep for the remainder of this)
/summon sheep 23 24 25
/summon sheep ~ ~ ~
The other way you could do it is to take advantage of a shulker's auto-align feature. You can summon a shulker, it will ...
Your command, /tp @s ^ ^ ^0.5 is being run in a command block. @s always refers to the executor, that is, the "thing" running the command.
Since your command is running in a command block, the "thing" running the command is the server. So, @s would not refer to you.
You can use /execute to change who the command is being executed as, ...
With selectors, all filters(or the values in the square brackets) go in one array(square brackets). It would be in the form of name=value,name=value,name=value and it keeps going until you don't have any other filters to add. So you need to combine team=goawayree with x=730,y=0,z=110,dx=50,dy=256,dz=50 in one array to make [team=goawayree, x=730,y=0,z=110,...
Remove these two brackets and insert a comma ,:
to end up with this:
Also note an interesting quirk about dx, dy, and dz. The axes of the box you create are actually one more than what you type in. So actually, 0 is a ...