Following are some online resource you can use to create different diagrams in the project

Sea Quail Database Diagram Tool (It will work in Chrome browser only)
https://chrome.google.com/webstore/detail/sea-quail-database-diagra/elkpialiknkiaebieojbgnhindepnlkg?hl=en

http://ondras.zarovi.cz/sql/demo/

http://www.dbschemaeditor.com/OnlineDB.aspx

http://creately.com/app/

https://www.lucidchart.com/pages/examples/uml_diagram_tool

http://www.gliffy.com/uses/uml-software/

http://yuml.me/edit/23db58a4

https://www.websequencediagrams.com/#