Urgent : Can I upgrade coldfusion9 to coldfusion2021 directly?

You cannot upgrade the ColdFusion software from version 9 to version 2021. However, with few exceptions, code that works on ColdFusion 9 will also work on ColdFusion 2021. 

To reduce the risk of migrating incompatible code, there are two things you can do:

1.  Study the list of deprecated ColdFusion features. Verify whether any of them occur in your code.
2. Run the Code Analyzer tool on your project code. To find the tool, open the ColdFusion 2021 Administrator, and go to the Debugging & Logging page. Use, as the analyzer's baseline setting, the oldest version of ColdFusion (usually v. 11).