How did you improve your vocal range and voice control?

I used to sing all the time and used to have a vocal coach but stopped because of Covid and after that multiple things like not having enough time, and also my vocal cords for some reason being more strained then they used to be made me too afraid to get back into it. I want to be able to sing high notes again but don't know/ remember ways to do that. I've also been struggling with my voice control/ power. If there are any tips or tricks I could do at home to improve either of those that would be appreciated!!