Your script file should look like:
Adjust the colored parts to match your requirements - path of TIFF file, insertion point, scale factor, rotation angle and target DWG file's path.
_NEW _IMAGE _A C:\\TiffFiles\\TiffFile1st.TIF 0,0 1 0 _ZOOM _E _SAVE C:\\DWGFiles\\DWGFile1st.DWG _CLOSE
_NEW _IMAGE _A C:\\TiffFiles\\TiffFile2nd.TIF 0,0 1 0 _ZOOM _E _SAVE C:\\DWGFiles\\DWGFile2nd.DWG _CLOSE
_NEW _IMAGE _A C:\\TiffFiles\\TiffFile3rd.TIF 0,0 1 0 _ZOOM _E _SAVE C:\\DWGFiles\\DWGFile3rd.DWG _CLOSE
Please take care that after _NEW you should let 2 spaces; also the script should end with an empty line. Save this file with SCR extension.
It is very important to don't have spaces in TIFF or DWG paths, since those will be treated as <ENTER>.
Call the SCRIPT command, you will be asked to point to the said script file.