When you install a new version of SSMS, you may have to reinstall the SSMS plugins (SQL Prompt, SQL Source Control, SQL Test, SQL Search) to get them integrated.
If the new install is SSMS 2016 or SSMS 2017 the plugins should already be available for the new SSMS install.
If the new install is SSMS 2014 or older, you will need to reinstall the plugins:
1. From Control Panel, uninstall the tools needed in the new SSMS install
2. Run the latest installer(s) for the tools
Note: SQL Prompt is not supported in SSMS 2008 R2