You aren’t too old to learn new things unless you suffer from dementia, and I don’t get that impression. I’m probably older (60) and I still learn new things in software development and sys admin constantly.

Find out what cloud provider(s) your employer is migrating to. Learn those, get certified, get involved in the migration. You have two to three years to learn some new things that at least relate to what you do now. Don’t stand around waiting for the ship to sink, as you put it. Get on the team, learn about cloud hosting, networking, security. Make yourself valuable to your employer rather than standing there watching your job evaporate.

You can read books and articles but the best way to learn is by doing. Most likely your employer will go through some trial and error figuring out the migration, which gives you an excellent opportunity to learn by doing.