初めまして！ 今日から、ここで文を投稿します。とりあえず、短い文を書きますが、将来もっと長い文を書きたいです。よろしくお願いします！
Hopefully that was comprehensible. I’ve delayed output for much too long, so I’m wanting to take my first baby steps into output. This seems like a decent place to start! Feedback is always welcome!
おめでとうございます！書きましょう！
Looks good to me 
I’m sure you’ll be writing longer and longer sentences in no time!
Protip: for longer sentences, just replace all punctionation with 〜て/で 
Protip 2 - tip pro-er: I give bad advice
It was! 
The only thing I would change is ここで to ここに, since you’re 投稿する to somewhere specific.
こちらこそ、宜しくお願いします！
で vs に has been the particle pair I struggle with the most, I feel. I never really know when it feels to right to use one versus the other. 
Thank you for the feedback! 
They each have a fair few use cases which overlap sometimes, mostly when referring to locations in relation to the verb.
As a general rule, で refers to where an action takes place, and に refers to what the destination is for an action.
So 公園に歩く = to walk to the park, whereas 公園で歩く is to walk in the park, basically.
This can sometimes get a bit confusing in translation: 東京で家を書いた and 東京に家を書いた both mean “I bought a house in Tokyo”, but with で the nuance is you bought a house while you were in Tokyo, whereas with に it’s the house that’s in Tokyo, but you might as well have been in Brazil when you bought it.
Does that help?
初めまして。ヲードカトです。これは文です。 
That does help! At the very least, it feels like something clicked into place. Now to turn that into using them correctly from here on.
ありがとうございます！
I think in this case 公園を歩く might work a little better for “walk in the park”, because walking and the park are still linked. With で, walking is independent from the park and the park becomes more of a background context.
I think it would be 東京にある家を買った。With に alone we still have only 1 verb.
Yeah, true. Bad example
Could be? It definitely feels more natural, I was thinking that as well, but I more or less lifted it from this StackExchange thread.
Maybe they’re just both bad examples 
You mean those with 中に and 中で? I’m not super confident with how to always use them, but in this case 中 does change things a little bit, I feel.
Edit: Note that I’m pulling stuff from my brain now. Would need to look for legit examples later 
今日PCでファイナルファンタジー４を遊び始める。日本語でゲームを始めて済まさないことが多いので、済ますといい。
No, further below:
Note that there are cases where both で and に are possible, but the nuance is different:
- 東京にアパートを借りた I rented an apartment in Tokyo (an apartment located in Tokyo)
- 東京でアパートを借りた I rented an apartment in Tokyo (when I was in Tokyo)
I did some extra searching for the 東京にアパート and came up with options which I think are a little clearer:
東京の賃貸アパート
東京の賃貸マンション
I would say that if it’s “an apartment in Tokyo” (and the reader/listener is not necessarily in Tokyo), 東京のアパート makes more sense. But I also don’t see any other response in the StackExchange thread to this and couldn’t find anything sensible with に 
.
何か書きたいと思うけど、元気じゃなくてコーヒーなども飲みすぎてしまった。T.T
できるだけ早く寝ねばならない気がする。
やっぱり今日は日本語が苦手になった感じだ。 
I loathe the 〜ねばならない grammar point. Can’t pronounce it properly sometimes.
Edit: 確かに didn’t sound right to me somehow…
日本語で返事したいけど、僕の思いをちゃんと英語から日本語へ訳するのがとても難しいですよ。もちろん、訳したくありませんが、まだちょっと早いですね？まあ、いいですよ。今日は、この文が足ります。
For what I would have wanted to say in Japanese if I could get the thoughts to properly form in my head: If you are feeling ill, I hope you get well soon! If you just meant that you were low on energy, I hope you get some proper rest! Take care of yourself! (Though of course that message goes for if you are ill, too. 
)
As for what I actually posted in Japanese:
Perhaps it’s best if I actually include an intended meaning? I’m not sure what the etiquette is!
Intended meaning:
“I’d love to respond in Japanese but translating my thoughts from English to Japanese is very difficult for me. Of course, I don’t want to translate (implied: so much as have the thoughts happen naturally), but it’s a bit early for that, isn’t it? Well, that’s okay. These sentences will suffice for today.”
The things I’m least sure about in how I phrased it:
Thank you! 
I think people mentioned this in another thread, but usually you can お大事に or 良くなってくださいね if you want to wish someone getting better. I think I should’ve clarified (with a translation, heh) that I actually meant just not feeling energetic with that 元気
I don’t think there are any requirements or expectations . Sometimes we include translations as that may help people figure things out.
I think you’re doing fine 
. It’s not like we’re all writing in keigo.
I would slap it in front of the verb for safety. There is also 訳す as a verb (to translate).
Yup . の for general conversions, こと for more conceptual stuff and もの for more physical stuff.
I only ever saw 間に合う being used in reference to time expressions. There is also 十分 meaning “sufficient, enough” and I’ve heard it used in news reports. This is what Goo says about 足りる:
So it feels like they’re really synonyms.
Nah, because you specifically mentioned coffee and needing to get sleep, I leaned towards the low energy translation. It’s my own overthinking that went, “Well, maybe they meant sick… Better cover my bases.” I don’t think a clarification is necessary just to sate overthinkers. 
訳す was actually what I intended to use when I wrote the sentence, and I think I just autopiloted the る onto there by mistake. Jisho tells me that there is a 訳する, but that’s it’s a “special” class verb… Not totally sure what that means, so I guess I know what I’m looking up for the next little bit.
Thank you for the feedback! It really is appreciated!
あ、ここに投稿するのは危うく忘れてた。今日、仕事は大変でしたから、なかなか疲れたです。それで、おそらく間違いました。 
お休みなさい、みんなさん！
今日、真・女神転生5をちょっとしました。ゲームのストーリーはちょっと難しいから、日本語の音声ですが、英語字幕です。誰かしていますか？
今、寝ますよ。おやすみ！
今日は、辛い食事 食べました
(yes I had to look up spicy)