Hi, 

You can follow following link for this:

https://youtu.be/GPhgxxwprA4

Hope it helps,

Thanks

You can't do it with a selection field, onchanges for selection fields and for the rest of the fields it will change the value of the field, not the set of values that can be selected on the value, for others fields like relational ones(o2m, m2o, m2m) you could set a domain to be apply for the field to change the resulting set of values to be selected by returning the domain for the field on the onchange, but the selection field is not the case as it's not a relational field and it will not be affected by domains