i cant figure out how to auto tag group of file at once, it will take forever if i have to do it one at a time.
Have look at the documenation about first steps:
and alos, perhaps a little more advanced:
In addition to ohrenkino's advice:
If your "group of file" is not an album, it is difficult to "Auto tag" them.
Most Websource scripts are designed to search for an entire album and tag all its tracks.
If you have a loose collection of tracks - for example the newest Top 40 Hits - it's almost impossible to "Auto tag" them automatically and without user intervention.
You always need to find an external source that matches your local files exactly.
Then you need a Websource script for this source.
Then - and only then - you can start "Auto tag" your local files.
Let us know what you were unable to figure out after reading the linked documentation.