It appears to me that 無礼 was directed at the guy who wrote この書き方は (which corroborates with the fact that the comment was deleted), not you. The guy who wrote この書き方は likely thought your expressions were strange/odd at times, but the other guy was implying that it would be rude to fault a person who was only in the beginning stages of learning Japanese over their writing.

In any case, you did fine navigating a lack of knowledge over grammatical constructions and creatively utilizing what you did know to fill those gaps to communicate with natives.

A few of the things I noticed that you may want to look at:

こんばんわ

This should be こんにちは. The last "wa" is the topic particle.

3週ぐらい

3週間ぐらい

目的は。。。日本人と話します

If you're expressing a desire, consider using the -tai form of the verb. Here, it would be 日本人と話したいです. Also make sure you keep consistent formality; predicating i-adjectives should be followed with desu when speaking in polite form.