Can’t я be omitted?
You can omit it, but it's not that common and it's unformal
If it's not accepted, you should report it. But it is not usual to omit it in the beginning of a sentence.
It is impossible to translate into Ukrainian because I can't use the Cyrillic alphabet so I have to write sounds, which is not the same. The crew who created this course didn't think it through.
Either : learn the Ukrainian alphabet or : get the Ukrainian alphabet keyboard and memorize the symbols so you can write in these exercises.
Answers written using the BGN/PCGN transliteration of the Ukrainian alphabet are accepted.