1.

How come when i duplicated part of my object and then deleted some of it, then put it in object mode, my main cursor, you know like whenever i selected move tool or something, remained in the centre. Instead of centering around the remainder of the that object that i DIDNT delet, it was still positioned around like elsewhere( as if the rest of the object wasnt deleted)

K well that sounds confusing. Uhh, so i duplicated a leg, and the deleted part of it so i just have the toe you know. And then when i put it in object mode so i could manipulate in uniform with the scale tool, my cursor was still like up top as if the leg was still there and not the toe. Like i know it will work if i select the faces- then the cursor will be there, but i kinda want to know why its doing this. It doesnt normally do this. So am i just crazy, or is this just like a small preferences problem?

2.

Also, what does it mean when you use the Union tool on two objects and nothing happens. Both of my objects are selected but refuse to Unionize.

3. And lastly, sorry, whats the difference between union and combine tool?

Thank you so much to anyone and everyone who takes the time to bother with my questions. THANK YOU!!