How should I weatherstrip my windows? Thx for your suggestions.

I am not very handy.  So I am not sure if I am doing the right thing.  If you could let me know, I would really appreciate it.

I went to HD and asked the people there about weatherstripping my windows.  I have a few huge windows.  A nice lady at HD suggested using weather seal tape on window trims.  So I got weather seal tape and taped the white drywall connecting to the glass (as shown in the picture).  I only used a few inches of tape as in the picture, since I am just trying to show you what i am doing.  I think I am supposed to tape all the edges.  I don't know what to call the white wall connecting to the glass.  I am using the word "drywall".  Is that window trim?

I also got Frost King plastic sheets.  That seems to be the only brand at HD.  I am going to cover the windows with the sheets after I tape the edges of the window. 

This is my first time weatherstripping my windows.  As you can see, I am very inexperienced.  So thanks in advance for your suggestions