high squeel when car starts goes away when put in gear

Hello, a good physical inspection will verify what is wrong, but it could be that the drive belt is squealing on one of the pulleys. The belt could be at fault, or a pulley could be worn or locking up on one of the components on the engine accessory drive. If the noise is not coming from the belt area, then further troubleshooting in another area will be needed. Unfortunately, since we cannot hear the noise in this forum or where it is emanating from, it is difficult to help further. Good luck!