Hi Ramona

Thanks for posting in Lucid Community! To check if Lucidchart has been installed in your Google Docs please click on the  Extensions menu in your Google Doc. From the drop-down menu click "Add-ons" and click "Get add-ons". If Lucidchart has been installed you should see "Installed" on the Lucidchart icon. 

To access the Lucidchart add-on you will need to click on the Lucidchart logo on the right hand sidebar. If it does not appear there you will need to make sure the sidebar is extended to access the integration (click on the arrow in the bottom right). Please see a screenshot below for this. 

For more information on the Lucidchart for Google Add-on feel free to check out this Community post here and our Lucidchart Add-on for Google Docs Sheets Slides and Gmail Help Center article.

Please feel free to let me know if this is not what you are looking for or if you have any questions about the above. I hope this helps!