My first ever campaign and I might have to DM

I have never played DnD before, I’ve wanted to play for years and I’ve finally found a group I can play with but I have no idea if I’ll have to dm.
In any case, I want to prepare hence this post.
I don’t want to buy the players handbook and dungeon master’s guide but I also suck at reading from screens.
Does anyone have a drive document I can simply change the font to a dyslexic version from?