Nothing you do in Canada will cause the loss of US citizenship so you don't have to worry about that.
In order to live with your husband, he should sponsor you for PR. He can sponsor you inland in which case you should be committed to staying in Canada throughout the processing time which can be months. After first stage approval which generally takes about 8 months, you can apply for an open work permit. Another 8 months or so to get PR.
If you apply outland, it is not important where you are. You can go to the US for a bit, work for a bit, come back to visit etc. The processing time for that is probably around 10 months to get PR.
After getting PR of Canada which is similar to the green card in the US, you would be able to live and work in Canada, you would have health care. However, you can not vote, you can be deported if you commit a crime and you could lose your PR if you spend too much time outside Canada.
As a visitor, you may stay up to 6 months at a time. You may not work or study although you may take short courses that don't grant college credits and can be completed during your visit, that is in less than 6 months. If you wish to stay longer than 6 months, you could apply to extend your visitor status.