8 – Store two text field values ​​(Text A and Text B) in Geofield (Lat & Lng) in the content of the same type of content

I have a content type with some fields. In that I have two text fields (Text A and Text B) and Geofield (Lat and Lng). So I need to store the values ​​of that text field in a geographical field (Text A-> Lat and Text B-> Lng).

I tried some logic based on entities, but it did not help.

Can anyone tell me how to do this programmatically?

Note: I have many contents (same type of content). In this sense, all the content has text field values ​​(Text A and Text B) and I need to store these values ​​in a geographic field that has empty Lat and Lng values ​​when cron is executed.