What is the difference between 시간 있어요 and 시간은 있어요 and 시간이 있어요 ?Feel free to just provide example sentences.

‘시간 있어요.’ means ‘I do have time.’

‘시간은 있어요’ is like ‘I do have time but..’ It hears like you do have time to do something but you just do not want spend your time on it.

Since ‘이’ is postposition particle, ‘시간이 있어요’ means same with ‘시간 있어요’ but the ‘이’ can be omitted. However, it sounds unnatural. When you say ‘I do have time’ in Korean, you usually do not say ‘시간이 있어요.’ Honestyly I do not know why but I do not say it like that and also I do not hear it.

There is one more way to translate ‘시간이 있어요’ which literally means ‘There is time.’ It is grammatically correct but as you know time does not physically exist so you don’t say ‘there is time.’