Try YTD Video Converter from GreenTree.
The are free and pay-for versions available for both, PC and Mac.
Be careful when installing. Be sure to check or uncheck the boxes in fine-print, to avoid having other unwanted software from being sneakily installed on your system.
There will be typically 3-4 pages (screens) where you may have to check/uncheck options.
If you don’t want to agree to something, click the Cancel (or equivalent) button.
This doesn’t cancel the install. It cancels the current web page (dialog box) and takes you to the next step in the install process. After 3-4 of these screens, you will see a screen showing the directory path where the program will be installed. Change it if you like. Click OK or Continue. You will then see the install Progress Thermometer, and the install process will complete.
I have been using this program for several years, with no problems other than having to outwit it during the install process, or where it may not be able to download a certain video format. It’s pretty good and easy to use.