I was shocked to hear that Yukimura Sanada almost forced Ieyasu Tokugawa into killing himself.
I was really surprised to learn that Yukimura Sanada almost pushed Ieyasu Tokugawa to the point of taking his own life.
ーI was shocked to hear that Yukimura Sanada almost forced Ieyasu Tokugawa into killing himself.
「真田幸村が徳川家康を自害寸前まで追い込んだと聞いて衝撃を受けた。」
I was shocked to hear that... で「…と聞いて衝撃を受けた」
forced ... into で「追い込む」
kill oneself で「自害する・自殺する」
ーI was really surprised to learn that Yukimura Sanada almost pushed Ieyasu Tokugawa to the point of taking his own life.
「真田幸村が徳川家康を自害寸前くらいまでに追い込んだと聞いてとても驚いた。」
I was really surprised to learn that... で「…と聞いて（知って）とても驚いた」
push ... to the point of ~「〜するくらいに追い込む」
take one's own life で「自害する・自殺する」
ご参考まで！
カナダ 
