Hi Krishna,
To achieve this you will need to set many to many association from your entity to ‘Account’ entity and use ‘reference set selector’ or ‘input reference set selector’ widget on the page and select this association in reference set.
Update:
Once you add ‘reference set selector’ or ‘input reference set selector’ widget, you will need to configure it based on your requirements. For example have a look at ‘input reference set selector’ used to select user roles on ‘Account_New’ and ‘Account_Edit’.
Hope this helps!