Brother, I want to allow users to input and select. How to do it now – php tutorial

I want to allow users to input and make choices. How do I usually do it now?
I want to implement it on the page. Certain data can be entered manually or selected. Is it better to use a drop-down combo box, or use a text box with a button, and click the button to pop up and select the value
Which one is better? Or is there a better way?
Do you think the button is better? But it is more complicated and a window will pop up. I don’t know how to do it
Is there any website that does this?
I want users to be able to input and select when filling in this data
Is there any website that puts a text box and a button to select?
Now we can allow users to input and select. How is this usually done? Is there any website that implements this function? I would like to refer to it
For example: for user name, I can enter: Zhang San
or a list will appear: Zhang San/Li Si/Wang Wu. . . . Go to select, I want to implement this function

——Solution—————– —
For simplicity, I use a drop-down menu and a text box

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a  
------Solution--------------------
Search  "js editable drop-down list"
http://topic.csdn.net/u/20091202/11/3bdeed60-3bce-4734-97f4-7153e421a642.html
There are many options to choose from
  ------Solution--------------------
Use Ajax, in  

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