[Home Phone] Detailed procedure to switch from Bell phone to dry loop / VOIP ?

Hi, I have phone service from Bell, DSL internet with TekSavvy. Condo has restriction where can't install a second phone line, so everything happens on the existing phone line. What sequence of steps should happen to: - port the existing phone number to a VOIP provider - convert the line to a dry loop Obviously need to minimize the downtime due to the restriction listed above. Thank you. Kleon