Hi Ronnie,
Thank you for your purchase.

These strings are in our Label Settings, go to the Settings page and you will see the Label Settings so you can change them there. 

At the moment for these for strings "employee", "employees", "service" and "services", it can be translated just on one language, we will add possibility to translate these strings in multiple languages in one of next versions.

About the string "Please select service" at the moment that is combination of string "Please select" (that you can find in translation strings) and label "service" from Label Settings. Like I said that we will add possibility to translate these strings easily  and also in multiple languages in one of next versions.

Words can be changed using POEDIT or Loco Translate for example very easily. I suggest you to install Loco Translate and then to translate these string.

If you want to use POEDIT then this is an instruction(example for french):

1. Download the Amelia plugin from CodeCanyon and save the .zip file on your computer.

2. Uznip downloaded .zip file.

3. You need to download and install POEDIT. 

4. After that open the program and open the file from the extracted folder on your computer ameliabooking/languages/fr_FR/wpamelia-fr_FR.po.

5. Translate all the strings that are not translated or translate strings like you need

6. Save the translation.

7. Go to ameliabooking/languages/fr_FR/ folder and copy these two files called wpamelia-fr_FR.po and wpamelia-fr_FR.mo back to your website in the location ../wp-content/plugins/ameliabooking/languages/fr_FR/.

Best regards.