With Crickit support in MakeCode, you should have a green CRICKIT block group available. Clicking on that group pops out various blocks for Crickit capabilities including those related to servo control as shown below.
For continuous servos, we will only use the middle (second) block called crickit continuous servo 1 run at 50%
Here is a simple MakeCode program that will run one servo connected to Servo 1 (as shown at the top right of this page) at full speed (100%):
For two continuous servos back to back on a robot chassis, run them forward at full speed by running Servo 1 at 100% and Servo 2 at -100% for 2 seconds then stop: