How to effectively use SMC Fan Control for Mac overheating?

That probably means the cooling intake or exhaust is obstructed, or there’s clogging internal, or a hardware problem.

I’m not sure why you think fan software would be useful.

Add-on management apps — add-on fan-control apps, add-on security apps, add-on VPN client apps, add-on cleaner apps, and other such apps — can themselves introduce various problems, including system load. As can failing hard disk drives, and other such possibilities.

Please download and run (free) EtreCheck, and share the results to the clipboard. Then open a new reply here, and press the Additional Text button that looks like a printed page, and paste and post the hardware and software configuration report here. From that, we can get a little more detail about what is installed and what is running here.

How to effectively use SMC Fan Control for Mac overheating?

You don't. Clever apps designed to circumvent the Mac's cooling system will ruin your Mac.

Post the EtreCheck report. Instructions: How to use the Add Text Feature When Posting Large Amounts of Text, i.e. an Etrecheck Report - Apple Community

Use MacFanControl to check the temperatures and slightly increases the Fan Speed.

https://crystalidea.com/macs-fan-control

+1 on etracheck, but I've never had a Mac that didn't need more cooling.:)