Show only pictures or videos in a mixed folder
Disk Sort by Zaweba has a kind filter that shows one kind of file at a time, such as pictures, video, music or documents, with folders always visible.

Pick a kind in the kind filter of Disk Sort by Zaweba and the file list shows only that kind: pictures, video, music, documents and so on. Folders always stay visible, so you can still move around the tree. Clear all filters puts everything back.
Mixed folders are the norm. A phone dump holds photos, videos and screenshots together, a downloads folder holds everything, and a project folder mixes documents with pictures. Filtering by kind lets you deal with one sort of file at a time.
Using the kind filter
Open the folder in the FILES tab. Thumbnails (Ctrl+1) suit pictures and video, while the detailed list (Ctrl+2) shows name, size, modified date, type and more. Choose a kind from the filter and the list narrows at once.
With pictures showing, thumbnails cover JPG, PNG, WebP, HEIC, GIF, BMP and TIFF, turned the right way up from their EXIF details. Ctrl+wheel or Ctrl+plus and minus change the thumbnail size, so you can fit more on screen or see each one larger.
Going wider than one folder
The filter works on any list, not only a single folder. Branch (B) lists the open folder and everything below it, flat, and Showall (S) lists every file in the scan. Pair either with the kind filter to see every video on a drive, or every picture in years of nested folders, in a single list. Esc returns to the open folder.
That is useful when photos and videos have been scattered over many dated folders and you want to gather one kind in one place.
Narrowing further
The name filter (Ctrl+F) accepts * and ? wildcards, so you can show, say, only files whose names start with a certain prefix. The photo filter limits the list to keepers, stars, edited pictures, a date range, a camera or a keyword, or to tagged files only. Filters combine, and Clear all filters resets them in one go.
Sorting helps too. Sort by name, date, size, type or date taken, and reverse the order if you want the newest or biggest first.
Doing something with the filtered files
Once only the files you want are showing, Ctrl+T tags everything shown. Then copy, move, zip, rename or delete the tagged files as one set. For example, show only video, tag the lot, and move them to a separate folder or another drive. Every operation asks first with counts. Moving to another drive copies, checks that everything arrived and only then removes the original.
For pictures, the filtered list is also a good place to cull. Press Enter or Ctrl+3 to see one picture at a time, mark keepers with the star or P, rate with 1 to 5, and use Delete all but keepers to send every other picture in the list to the Recycle Bin after confirming. Because the list is filtered to pictures, the videos in the same folder are not caught up in it.
A few habits that help
Check which filters are on before acting on a list. A forgotten date range or keyword filter can hide files you expected to see, and Clear all filters is the quick reset.
If you want to see how much space each kind takes before you start, the TYPES tab totals the open folder by type and extension. Disk Sort by Zaweba is free and works offline, and its filters never change the files themselves, only what is shown.