Welcome to the forum, satinejaune!
Try these recipes if just starting out:
https://www.morebeer.com/products/porter-extract-beer-brewing-kit-5-gallons.htmlhttps://www.morebeer.com/products/german-hefeweizen-extract-beer-brewing-kit-5-gallons.htmlThese kits contain no yeast. For the porter I would suggest Lallemand Nottingham ale yeast. To turn the hefeweizen recipe into a Belgian white, simply use WLP400 yeast instead of a hefe yeast, or you could even try Lallemand Belle Saison yeast if you want a dry yeast option. These recipes and yeasts will get you what you want.
I thought for sure you were going to ask about how to add the fruit flavors, to which I would have responded:
1) Use real blackberries, about 1 pound per gallon, added at the end of primary fermentation, then allow to ferment for a couple of weeks.
and
2) At the end of Belgian white fermentation, soak elderflower leaves and the zest of about one lemon in vodka for at least 5-6 hours or overnight, then add just the flavored vodka to your finished beer, and package immediately.
Cheers and good luck. Hope you get what you like out of all this. Cheers.
EDIT: Looks like you will also need a small steeping bag. If you don't already have one, try this:
https://www.morebeer.com/products/drawstring-mesh-bag-8-15.html