Fix: Visual Studio 2022 Intellisense not working
This issue can be quite a frustrating one if you happen to encounter it and it can really slow down your dev productivity.
If you have tried the obvious solutions like restarting Visual Studio, upgrading to the latest version of Visual Studio, or any of the obvious low-hanging solutions and no luck perhaps try the steps I will list below. Please note there is no one solution to this problem, this is just but one possible solution that may or may not work for you.
Step 1: Go to tools and select import and export settings

Step 2: Select Reset all settings then press next

Step 3: Save the current settings then click Next

Step 4: Select the collection of settings you want to reset to, then select Finish

A quick restart should help get Intellisense working fine and you should be good to go.