While the OSOYOO Pie Robot kit comes with a basic screwdriver and hex driver, they aren't great quality and it doesn't include a tool to tighten the hex nuts. Additionally, if you choose to use the optional M2.5 hardware for mounting the circuit boards to the robot then you will most likely need a smaller hex driver. The Kaisi 70 in 1 Precision Screwdriver Set is a good quality tool set that includes all of the driver bits that you will need. It also includes a pair of tweezers which will be handy for picking up the small hardware.
Since you will be working with electronic boards, it is best to have an ESD mat and wear the ESD wrist strap when handling the electronic boards so that you don't damage them. The iFixit Portable Anti-Static Mat is a good option that will provide an ESD safe working area to build the robots.