I highly recommend getting some quick-grip clamps, the ones with a trigger-grip like this: https://www.amazon.com/IRWIN-QUICK-GRIP-1964758-One-Handed-Clamp/dp/B001DSY4QO/ref=mp_s_a_1_1?crid=2V307O9UDOGYS&keywords=irwin+clamps&qid=1639108097&sprefix=irwin+cla%2Caps%2C88&sr=8-1

Trying to screw down a C clamp while holding multiple pieces of wood together is an exercise in frustration. You can also get some spring clamps (look like plastic pliers or scissors with plastic pads) for extremely cheap; I got a bag with a couple dozen of assorted sizes for ten bucks. They don’t have the clamping pressure of a big F clamp or a pipe clamp, but they’re quick, easy to use one-handed, and can hold things in place long enough for you to get the bigger clamps in place. They’re also ideal for smaller projects.