Even if I could go back 4 years and study pharmacology, I might still say that it was better to have studied engineering.
ご質問ありがとうございます。
"Even if I could go back 4 years and study pharmacology,"=「もし4年前に戻れて薬学を勉強したとしても、」
"I might still say that it was better to have studied engineering."=「工学を勉強したほうが良かった、と言うかもしれない。」
ご参考になると幸いです。