Hi Nelly,
Glad to hear that you just started learning French! It's certainly a wonderful language and lots of fun. With regards to your questions,
<ol><li>There aren't actually 'silent letters' per se. But rather letters that are not pronounced <em>within the context </em>of certain words. </li></ol>
For example, blanc (white) is pronounced blONG, so the C & N are silent <em>in this case</em>.
However, in donc (therefore), the C is pronounced. So it completely depends on the word.
Pertaining to 1,2: my approach with French was to start with some basic rules of pronunciation and grammar, as taught in many beginners' videos on Youtube. Learning pronunciation through reading might be quite inconducive in French, given the incongruity between it's writing system and pronunciation. However, the important thing (at least for me) was to NOT stick for too long with grammar, but rather just jump to videos of real French people speaking, and put on the YT Close Captioning/Subtitles system. Slowly you will get there.
3.Contrary to what people think, I don't believe that French is difficult to pronounce at all. French has a very limited base of sounds -an/en, -in, -on, euh, and is quite 'neutral' as well, so once your brain figures out the correlations between the written words and sounds, it shouldn't be that difficult.
I personally know people who have picked up the language at 23, and can speak with no trace of accent at 25. I wouldn't be able to say the same about Spanish (especially with the Rolled Rs and the preponderance of tongue movements'. However, I'd say not to worry too much about pron at first. With enough listening to people speaking, you will get there naturally.
Hope this helps!
Matt