Amy from the Altestore.com and
Will Prowse both have a lot of content that is very beginner friendly and makes it easy to understand the basics.
I encourage you to not just start with the basics of solar but go a bit further back and start with understanding the basics of electricity, and the different units used. It makes it a lot easier to understand the more complicated stuff a little further down your learning path if you have an understanding of what Volts, Amps, Watts, Watt-hours, and Amp-hours are and how they relate to each other.
This is the video that finally got through to me and gave me an intuitive understanding, its long but worth watching. If you want something simpler and more bite sized, start with the Will Prowse videos I linked to above.
Once you move beyond the very basics, there are a lot of other good resources for planning your system. I recommend the videos from Pacific Yacht systems, specifically
this on how to design your electrical system, and this one on
fuses and protection.