In an entity create form, how to use dropdown/input-reference-selector of another entity?

I have an  entity A with columns col1, col2, col3 all the columns are of type string and I've to create a form for entity A for inserting new objects into it. For every column in the form I have to display a dropdown from another entity B having only one column of type string. For every column user can select the value from the entity B or user can enter the value directly. How can I achieve the above scenario and is there any changes required for my entities and their column data types?
1 answers

I think you would need to create 3 associations between A and B (all *-1).

Do you need to store a value in Col1 on entity A? or is it sufficient to show the associated value from B?

If it is enough to show, you don't even need Col1, because you will show the value from the string attribute on B on your form.

If you need to store it, you can use an on change microflow that copies the value from B to col1. And do the same for the other columns as well.

Hope this helps.