You will need a video DVD authoring app to create and burn the movie to disc so it can be played on a set top DVD player. Go to the App Store and do a search for video DVD. You'll get a list of many potential candidates. There are a number of free apps and demo apps (puts a watermark over the resulting video until the app is purchased). Most can save as a disk image so you can follow this workflow to help assure the best qualty video DVD:
Once you have the project as you want it save it as a disk image via the File ➙ Save as Disk Image menu option. This will separate the encoding process from the burn process.
To check the encoding mount the disk image, launch DVD Player and play it. If it plays OK with DVD Player the encoding is good.
Then burn to disk with Disk Utility or Toast at the slowest speed available (2x-4x) to assure the best burn quality. Always use top quality media: Verbatim, Maxell or Taiyo Yuden DVD-R are the most recommended in these forums.