Updates from the WordPress repository are easy: login to the dashboard and update. But with paid themes and plugins it's harder: most of the times they offer no connection to a repository, so manual updating (mostly with FTP) is the only option.
Envato offers a way to connect a website with your ThemeForest account. This isn't perfect but will make the process a little bit faster.
- Install Envato Market plugin: https://envato.github.io/wp-envato-market/.
- Create a token at https://build.envato.com/create-token/. Enable these 4 permissions: 'View and search Envato sites', 'Download your purchased items', 'List purchases you've made' and 'Verify purchases you've made', click agree and Create Token.
- Save this token in a password vault.
- Add the token in the WordPress back-end. Choose the global OAuth token to show all downloads. Choose the personal OAuth token to show only one item.