if one method has three if /else, and if the first test is true do we just skip the others test and statements?

If the the first part of an if/else statement is true is does skip over the next parts.

If you mean code like the following, then yes, if x < 5 is true, then execute its body to output an A and skip the rest. So x = 2 outputs A.

if (x < 5){
System.out.print("A");
} else if (x < 10){
System.out.print("B");
} else {
System.out.print("C");
}

If you mean code like the following,

if (x < 5){
System.out.print("A");
} else {
System.out.print("B");
}
if (x < 10){
System.out.print("C");
} else {
System.out.print("D");
}
if (x < 20){
System.out.print("E");
} else {
System.out.print("F");
}

In this case, any value of x will ouput 3 letters because each if...else would output a letter.
If x = 2, output is ACE. if x = 8, ouput is BCE. If x = 21, output is BDF.

If any of the if/else conditions are true you execute the block of code under that condition. Then you can skip the rest of the conditions.