Ive just startee getting into privacy, but i had a few questions.

1. I havent switched operating system yet due to fear of losing my data. I have a lot of pictures, contacts and messages i dont want to go missing. I have a one plus and i really love it. I do not want a pixel phone. Is there a way i can maintain privacy without changing phones?
2. If i delete google play services, will my phone not work correctly?
3. I have been replacing my apps with open source apps, is that helpful?
4. What vpn should i use? I have malewarebytes.