Hi. The ' I can' is the one English speakers would use. The second suggest some kind of repeating for no real reason. These sentences only talk about now so present perfect doesn't work. I live here now . This is about now so no present perfect. I have lived here for three months. The action began in the past and is still happening now. There is a connection between the past and now so present perfect is possible.Does that help? Please ask if you have any more questions

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