Trying to use an LCD 1602 to display, but I don't have a 10 KOhm potentiometer
Yes. All a potentiometer is, is two resistors end to end.  The "wiper" is the join between the two resistors.

It doesn't matter too much what value potentiometer (and hence what value resistors) you use, as long as it's "around" the 10kΩ mark (100kΩ should be fine, 50kΩ, 1kΩ etc - anything below 1kΩ may not work) - what matters is the ratio of the values of the resistor.