First if you already have a smart tv, go to it's apps menu and search for your service. All major services will be there. I know one exception currently is HBOMax on an LG tv not bing available.
If you do not have a smart tv you will need a streaming device like a Roku, TiVo stream, appleTV, amazon fire, or some other Android tv device. I have both Roku and TiVo stream sticks and recommend both. One note is currently Roku and YouTubeTV are not getting along so you have to install the YouTube app to use youtubeTV. These devices are between $25 and $50 and can be found at most stores that sell televisions. There is no subscription required to use these devices for your streaming device.
Services to walk through this process are available, contact me if you have any questions.