I have been watching Naruto online, and there are no episodes available to watch after 301, even though I know there is a big war on that episode. Are there any more Naruto episodes? People have been saying there is an episode 700, but is that all manga?
There are 220 episodes in Naruto original anime series, which has been completed. Then Naruto Shippuden, which has 500 episodes in total. The series finished airing on the 23rd of March, 2017.
There are 700 manga chapters and an extra 10 chapters in the Naruto: The Seventh Hokage and the Scarlet manga, which is set several years ahead of the final chapter (volume 72) of Naruto.
With the conclusion of Naruto, we now have its spin-off/sequel, Boruto: Naruto Next Generations. This is currently airing on Crunchy Roll and is 18 canon episodes in as I am writing this. Also the manga is available to read for all the purists.
For a question with ~60k views, I found this to be surprisingly un-updated. Community bumped it up in my feed and I decided to answer.
Naruto the Anime, as it is defined includes 2 series, 11 movies and over a dozen OVAs. The full list is available here List of Animated Naruto Media
The first Naruto anime adaptation premiered in Japan on TV Tokyo October 3, 2002, and ran for 220 episodes until its conclusion on February 8, 2007. It led to a first timeskip of two years. 3 movies were also released with the original Anime.
Naruto: Shippuden is the sequel to the original Naruto anime and covers the Naruto manga from volume 28 on. The TV adaptation of Naruto: Shippuden debuted in Japan on February 15, 2007, on TV Tokyo, and concluded on March 23, 2017. The series ran for a total of 500 Episodes. There were another 8 movies accompanying the series, the last of which set stage for Naruto's son's solo series, Boruto:The Next Generations which is currently airing. (5 Episodes and counting).
Thus, there is no Episode 700 since the Original run and Shippuden are seperate series. Total episode count of Naruto finished at 720 Episodes. Boruto is not considered to be of the same continuity because Kishimato is no longer writing the series but is more of a supervisor.
You must be following the Naruto Shippuden English Dub Episodes. At the moment, the English Dub episodes are lagging far behind the Japanese episodes as far as the anime is concerned. Like @mirroroftruth said, the Manga is the latest episode.
But in English Dub, the latest is episode 301 and more are coming up. The next one is expected to be aired on July 11th. So you'll have to be patient.
As for Japanese, the latest one aired yet is episode 418.