Thanks for posting in the community! While there are several types of diagrams governed by conventional design, such as org charts or entity relationship diagrams, a product road map has much more flexibility both in content and design. For this reason, Lucidchart doesn't automatically place shapes in the diagram with source data. However, if you're interested in using the Product Roadmap template, you can take advantage of the already existing shapes and swimlane grid with your own data by selecting Replace Dataset from the Manage Data menu. Then, you could drag your own data onto these same shapes and replace the template data with your own.
However, you may also want to create your own product road map from scratch. For guidance here, please take a look at our Data Linking article and let me know if you have any specific questions.