What are cups and spoons?
A lot of the recipes I use come from America, where they have no idea how to measure anything properly so tend to use volume-based measurements called cups.
I’ll give approximate metric conversions for cup measurements but you might prefer just to bite the bullet and get yourself a set of cups — they can be found relatively cheaply online. Make sure your set includes, full, half, third and quarter cups.
You’ll also see tea/tablespoon measurements which I’ll leave as-is but if you don’t already have one, a set of proper measuring spoons is a great investment. You’ll want a set that goes right down to a quarter-teaspoon and includes a half-tablespoon too.
Your oven is a unique snowflake, and each recipe is special.
Every oven is different. Some burn hot, some cool. Some heat efficiently in all areas, others have hot and cold spots. The only way to really get to know your oven is to cook in it, as if you need an excuse.
Recipes are also highly variable — some will come out looking horribly underdone but then firm up perfectly on cooling, others will need cooking until they seem done.
Usually when trying a new recipe I’ll break the baking down into smaller batches so I can see how the results look before committing to baking the whole lot. That way you can make adjustments easily — if the first batch comes out overdone, bake the second batch for a few minutes less, then see how they come out and keep tweaking as necessary.