How to " select it all " and put it in the timeline ?

I can select all pictures at the top level ( like in the WDW collection),
but each and every video needs to be dragged so I have to scroll all the
way up - to the left - select it. then drag it to the lower right ,etc.

Is there ANY way to speed that up ?

After spending an hour or two getting all the pictures,videos from a
recent trip into Collections in WMM, I have
" East Coast Trip"
and under it
" Florida" then in that I have
- WDW
- Miami
- Keys etc
then GA
--Savannah
--Hilton Head
then SC
Charleston , etc
( so "left screen" is now less messy)
what I'd like to do is:
click on "East Coast Trip"
"Select All" and drag it to the timeline.
Seems like a common "thing to be done".

Thanks,
Bobb