Migrating a website without breaking existing url and seo

I have a wordpress website hosted on digital ocean.

Since I don’t have a c panel on my current droplet of digital ocean, I am currently planning to create a new droplet / server with C panel and to redesign the existing wordpress website on the new server(droplet) with new theme.

The problem I am facing is, currently my website is getting a traffic of more than 5000 visitors per month. And I am hesitating in changing the server (droplet) because I don’t really know the steps to follow for not losing the traffic.

Kindly guide me with steps How to do the same without losing seo and traffic.

I also have doubt that :

1) If I delete my existing server and create a new one, I might lose the rankings which I am currently getting on google.

2) Will it be okay with google if my wordpress website stays down for a day or two (during the time while I create a new droplet / server )

3) If I successfully created a new droplet , Installed wordpress , used same articles but this time changed the url (remove category while creating same posts on new hosting) and redirected the older urls to new urls using redirection plugin, will it work? will my article rank somewhat the same way as it was previously?

I really need some support here. Expecting answers to all doubts mentioned.

The page I need help with: [log in to see the link]