First: Attachments are not allowed on this list;
you'll need to upload it to some on-line site, then send the
URL; for us to have access to it.
Second: any PP made with MsFt programs, can be opened using LO's
Impress program; if you click on the PP & then choose 'Open', you might
only see the PP running ...
but if you open the LO program, -> choose its Impress option, ->
you will have a blank presentation to which you can then upload that as a
'file';
at this point, you may make any changes you wish then 'save as' with
whichever extension you wish.
Hoping this helps,