Go on to Youtube and search for ChrisFix's channel. When I started DIY, I found his videos very good for the layman who is started out in automotive DIY.
As someone inexperienced, you want to be as safe as possible by working on a flat surface, working on an incline is very dangerous. Having said this even on a flat surface you will need chocks when jacking a vehicle. The jack is only sufficient to raise the vehicle and change a tyre. If you're going to work under a raised vehicle then use jack stands as they are more stable. A jack can fail under prolonged load, while jack stands are rated for specific loads.
If you're DIYing because of cost saving, I would say go to ABM and you will get increbible pricing as a fanatic.
If you're DIYing because it's something you're interested in then that's great! Youtube has endless video of going about this and you may find forum members willing to come and assist you.