My Jjournal entry about Florece

I'm planning to write a journal about my stay in Florence from October 28 to November 15, 2008.

My Jjournal entry about Florence

since your title is in sentence case, "journal" doesn't have to be in capital

I'm planning to write a journal entry about my stay in Florence from October 28 to November 15, 2008.

他にも可能： I'm planning to write a journal about my staynarrate my sojourn in Florence from October 28 to November 15, in 2008.

The original is possible; the version above has more flavour.

他にも可能：Ideally, I'd like to finish ithis narration by the end of November, but I’m unable to catch up on itthat task seems impossible.

他にも可能：In fact, the days just keep slipping further awayit has taken me longer and longer to complete this task.

I haven’t even finished writing about themy second day yet.

I'm planning to write a journalpost about my staytime in Florence from October 28 to November 15, 2008.

I'm not sure if "journal" is the write word.

Do you mean that you are going to write a post here on LangCorrect about the trip? If yes, then the word "post" is more appropriate.

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You can use the expression "my stay" - the grammar was perfect!

However, since it was only 2 or 3 weeks, using something like "my time" or "my trip" would be more appropriate. It depends, though.

Ideally, I'd like to finish it by the end of November, but I’m unable to catch up onstruggling to get around to it.

or:
"I'm struggling to find the time to write it"

In fact, the days just keep slipping further away.

I haven’t even finished writing about the second day yet.!

My Journal aAbout Florece

In most instances / style guides, “About” will be capitalized; the exception is MLA format.

You can also check here: https://capitalizemytitle.com

Ideally, I'd like to finish it by the end of November, but I’m unable to catch up on it.

The former sentence “I’m planning to…” indicates you haven’t yet begun to write. Here saying “catch up” implies you have begun, but are behind schedule.

If you HAVE started, the former sentence would want to say “I’m in the process of…” or similar to signal the writing is underway. Or you could rephrase “I’m writing a journal and planning an entry for every day of the trip…” to be even more explicit about your current status and future status.

If you HAVEN’T started, here you’d want to say “…behind schedule / struggling to get started / etc.” to signal that you haven’t begun, but you’re behind schedule.

My Journal about Florence

Ideally, I'd like to finish it by the end of November, but I’m unable to catch up on itmeet the deadline.

Another way of putting it.

Ideally, I'd like to finish it by the end of November, but I’m unable to catch up on it just can't seem to keep pace.

In fact, tThe days just keep slipping further away.