Version 7.6? I assume a typo, the lastest version is 7.5.

Unfortunately you can't delete a point from a polyline. You will have to draw a new line or leave the point in the middle of a straight line.

Don't depend on what an AI says, they are very unreliable for finding answers and often plainly wrong. For example this question about removing a point. You can add and remove points on a room and the AI focusses on "remove point" and doesn't take into account that a polyline is not the same as a room.
Search this forum and you will have a much better chance of finding a correct answer.