My two friends and I leaned against a fence, it broke and we fell into a river and I got a cut on the bottom of my foot.
この場合、次のような言い方ができますよ
ーMy two friends and I leaned against a fence, it broke, we fell into a river, and I got a cut on the bottom of my foot.
「友達と3人で柵に寄りかかってたら壊れて、川に落ち、足の裏を切った」
to lean against ...「…に寄りかかる」
to fall into ...「…に落ちる」
to cut on the bottom of one's foot「足の裏を切る」
ご参考まで!