It's a learning curve. Start with the bits of regular maintenance you need to do, and go on YouTube to learn how to do it. Besides Sheldon Brown's webpage, Park

It's a learning curve. Start with the bits of regular maintenance you need to do, and go on YouTube to learn how to do it. Besides Sheldon Brown's webpage, Park Tools make great maintenance tutorials. Start with tuning brakes, to changing chains, and tuning derailleurs, changing cables, taking bits off for cleaning. It will feel cumbersome, and a few times you will get yourself into a mess and end up taking a more-broken bike to the shop. But you'll get there eventually.