Resolved questions
If you check these 3 sentences, I'll be very glad! Help me, please.

With minor corrections each sentence would be correct.
1. .....the child in such a tone.
2. sentence is okay as written
3. How much time will you be travelling before you get home? or... before getting home.

However, they might sound more "natural" as follows:

1. I won't allow you to talk with this child in such a tone.
2. At this time tomorrow, I'll be cleaning the flat.
3. How long will you be traveling before getting home.

Also, I used the alternate spelling of traveling (ONE "L") but two "LL's" is also correct.

You're not going to talk with that child with such a rude tone. I wont allow it!
At this time, tomorrow, ill be doing some cleaning up in my flat.
How long will your travel take before you get home?

Do you want the sentecences to be corrected? (people have already done it so). Or... do you need an explanation on the differences among the various Future Tenses available in the English Language? (Simple Future, Future Perfect, Future Continuous, etc.)