If your Macbook trackpad is not working, there are a few steps you can take to troubleshoot the issue. First, remove any connected peripherals. Then, check for software updates. Third, reset the System Management Controller (SMC).
Finally, restart your Mac. A quick restart can often fix a lot of errors and technical issues, including issues such as the touchpad not working on a Mac. To do this, select the Restart option from Apple's main menu. Reconnect the power cable and wait another 5 seconds before releasing it after 20 seconds when you hear the startup sound or see the Apple logo.
Officially, it's not possible to reset the SMC on an M1 Mac because the M1 chip now manages the functions. However, many users report that something similar to an SMC pause can be done by completely turning off the Mac and waiting 30 seconds before turning it back on. This process simply removes any existing trackpad properties files that may be corrupt. When you restart your Mac, your files will be restored.
Updating your Mac's touchpad firmware may also help to resolve the issue. While there is no 100% guarantee that this will fix it, it is worth trying if other methods have failed.