Is there a giant and subtle difference in [fors] in [provide for and prepare for]

Hi,

Could any native right me to help me ?

I have a naive idea below the narrative.

A. In the examples ---about [provide for], we find [for] shows that something, that is provided, is necessary for one to do something. ----

[provide something for one to do something else]

---[one to do something else] as a result;

---provide something as a reason for one to do something else;

----something provided as the real subject;

B. In the examples----about [prepare for], we find [for] shows that someone or something is put into a suitable state with a purpose of ....

[with a purpose of ....]---

in regard to...;---[for] shows the real subject;

A. The plans provide for road traffic increasing to twice its present volume. ----[road traffic increasing to twice its present volume] as the result of something provided;----something provided as the real subject;

A. to provide for all eventualities ------[all eventualities] as the result of something provided; ----something provided as the real subject;

A. The possibility of the book being translated is provided for in your contract. -----[the possibility of the book being translated] as the result of something provided ----something provided as the real subject;

B. preparatory talks to clear the way for settlement -----talks that is prepared for / in regard to clearing the way for settlement;---[to clearing the way for settlement] as the real subject;

B. several meetings preparatory to signing the contract -----several meetings considered as being prepared for / in regard to signing the contract; ----[to signing the contract] as the real subject;

B. We must be prepared for all eventualities. ----We must be put into a suitable state for / in regard to all eventualities.----[all eventualities] as the real subject;

B. course that prepares students for the English exams -----stidents are prepared for / in regard to the English exams----[to the English exams] as the real subject;