You can print any project by clicking the ( i ) button, then clicking click ...More and selecting the Print option.
To print a task, open the task, click the 3 ellipses (...) in the top right corner of the task window and click Print.
Alternatively, to print a project in MeisterTask please open it, then press ⌘Ctrl + P. The same stands for a task, please make sure to open the task directly in your browser.