Is it a screw in whammy bar? Is it a snap in that pushes in at different heights? Does it have a outer jacket that screws over a threaded protruding piece of metal? What guitar brand and model is it would be the first thing to mention. A lot of variables but never be ashamed to ask. It’s is better to ask than not to ask and remain in the dark. Not enough input for a good answer. Don’t force it or try to "make it fit" either it belongs on it or not. Sometimes people have a guitar sold to them and it is threaded standard and some metric too. If it is a threaded one. Some pop down in there and if you push more it goes in farther. Kind of adjustable height thingy. : i know this is not the smartest question to ask but i got awhammy bar and i cant make it fit in the hole of the bridge and i dont want to mess up the bridge bacause they are expencive so i wanted to know how you are supposed to put the bar in the whole

It’s always possible that you do not have the right bar, or that it is faulty. The thread spacing might be different. Just to give it one more try, first check that it is not a left handed thread, which would screw in anti clockwise intead of the usual clockwise. Unlikely but possible. In any case, line the threaded part of the bar up with the hole, and while gently pressing it in, slowly turn the bar in the opposite direction to the direction that would screw it in. When you feel a slight click, you know you have found the end of the thread, so immediately reverse direction and it should screw in. If this doesn’t work your bar doesn’t match your bridge, or one of them has a damaged thread. If the bar’s thread is damaged this should be visible, perhaps with some magnification. You might be able to fix it with a small file. If it’s the hole that’s the problem it would need to be retapped. Good luck.