Where to start,well i "house" am not very good at art and neither am i at writing,so i just joined this jam to push my self to learn the mentioned skills,but i just can't get any ideas,don't get me wrong i can and i have made games in a limited amount of time but this is kind of different,in other "normal" game jams you can create a prototype for mechanic,but in a jam about visual novels you can't write the introduction of a story and expect to have a good game,and the art is a whole other beast,so do you recomend any free learning material?and what are some pro tips that i should know?Anyways thanks in advance,bye!

For a first VN, I would recommend keeping the story short and with a few endings/choices as possible. Just to get a feel for the writing.

Here's a very brief look on short story outlining and conflicts.

And a much more in depth series on coming up with a story and how to plan and structure it.

I think once you have an idea of the story outline, it'll be easier to figure out the kind of art you're looking to make.