i went to company for the first time in a week. ?
i have not gone to company for 1 week since
i went last time ?
its been for 1 week since i last went to company. ?
I went to work today for the first time in a week.
I haven't been/gone to work for a week.
It's been a week since I last went to work.
ここでは「会社」は company を使うより work と言った方が自然な言い方になりますよ。
ーI went to work today for the first time in a week.
「今日1週間ぶりに会社に行った。」
ーI haven't been/gone to work for a week.
「1週間会社に行っていない。」
since I went last time を付けなくても、上の例文にそのニュアンスがすでに含まれています。
ーIt's been a week since I last went to work.
「最後に会社に行ってから1週間が経つ。」
It's been for 1 week ではなく、It's been a week と言うと良いでしょう。
ご参考まで!
It had been one week since the last time I came to work.
ご質問ありがとうございます。
この場合、「[一週間](https://eikaiwa.dmm.com/uknow/questions/54500/)ぶりに会社に行った」と言いたいなら、簡単な英語で「I went back to work after one week.」と言います。
また、別の言い方で「It had been one week since the last time I came to work.」でも言えます。
ご参考になれば幸いです。