Watch some GCN videos, buy some tools, and get to know your bike. There are very few routine jobs on a bike that are beyond the capabilities of a home mechanic. It can be very rewarding. Yu may make mistakes as you learn, but it takes some effort to do any actual damage.

Find a small local bike shop that you trust and ignore the official "warranty" and "service schedule". Anything that is beyond your abilities should be a quick and easy job for any competent bike shop.

Bikes should be simple, robust and reliable.

In a lifetime of cycling, I've used a bike shop for repairs/servicing only twice: once to build a new wheel, and once to cut a steerer tube. I could have done the second of those myself but the shop charged me less than the cost of the cutting guide I was going to buy.