Yes, they will change if they are fields of type calcualtion.
No, they will not change if they are number fields with an auto-entered calculation.
This second option may be the way to go if you do not want changes to the value in the global field to update the computed value in your field. You can convert a calculation field to a number field with an auto-enter calculation very easily. When you change it to type number the current value of the calculation is stored as the number in the field. If you then open field options and select the options for an auto-entered calcualtion, you'll find your original calculation from the calculation field already entered for you.
It means that if I use a field with auto-entered calculation, the field will stores value even if the global fields has be changed?
Do a few tests and see what works best for you. Is the global field defined in the same table as the data field? Did you select or clear the "do not replace existing value.." option?
These details are key to what will happen when the value in the global field is changed and how it will function for you. With "do not replace existing value" enabled, the initial value computed when the record is created is the only value you'll see. I don't know if that works for you or not.
If you define the global field in a different table, changes to it will not update this field in existing records even if the "do not replace..." option is cleared for that field.