I am looking into the possibilty of creating a flow that will remove a part of a string inside a variable or field but I am unsure how to do it. 

I currently have a flow that updates a text field with 'hello' on the service contract when a record in another object is created. It also adds 'hello' to the end of the field if it is already populated. 

I would like to introduce a flow that will check whether the record is marked as closed where it will then remove 'hello' and replace with 'bye'. 

I would also like it to remove the 'hello' if the status of the record is marked as retained. 

How would I go about doing it? I would prefer not to add any additional fields

I am looking into the possibilty of creating a flow that will remove a part of a string inside a variable or field but I am unsure how to do it. 

I currently have a flow that updates a text field with 'hello' on the service contract when a record in another object is created. It also adds 'hello' to the end of the field if it is already populated. 

I would like to introduce a flow that will check whether the record is marked as closed where it will then remove 'hello' and replace with 'bye'. 

I would also like it to remove the 'hello' if the status of the record is marked as retained. 

How would I go about doing it? I would prefer not to add any additional fields