回答
This is not a piece of advice to you I'm talking to myself for my practice of writing skills.
please refer to the site. you can decide it by yourself with confidence unnecessary for any other opinion.
Quara
Agree with — someone.
I agree with you now.
Agree on — a point or issue.
I agree with you on this point.
Agree to — a proposal.
His partner asked him if he agreed to the proposal.
:weblio.
agree to(1.b,c) - proposal,
agree with(2.b) - person
:What's the difference between 'agree with', 'agree on', and 'agree to'?
https://www.quora.com/Whats-the-difference-between-agree-with-agree-on-and-agree-to
:the definition of the word 'agree' on the weblio dictionary.
https://ejje.weblio.jp/content/agree
この質問に回答する
「私の父は私の計画に同意してくれるだろう」を英訳するとMy father would agree with my plan.と某教科書にありましたが、My fahter would agree to my plan.ではどのようなものでしょうか。むしろ、私はMy father would agree to my plan.の方がよいと思うのですが、ご教示ください。