Hello from Berlin!
Look into your wardrobe case what seems suitable for the woods, into the attics and sheds of your family and older friends if you find there old military equipment or similar old and robust things, if not search the flea markets in your area or order a bit stuff from a military surplus shop and just start an expedition into the jungle at the end of your bus line the first weekend when you get more than 10°C in the night!
Try out what comes to mind and practice as much as possible to get own experiences.
You need to put together approximately this equipment here below. Take what you already have instead of investing a larger amount of money. Avoid civil equipment. Every military equipment from any western army will suit your needs and probably will last you a lifetime. I guess that you will get Spanish army equipment for the lowest prices and will make the best deals. I don't know it though.
Take an old woolen blanket or a used Tropen sleeping bag made by Fecsa, that's surely issued to the Spanish army. They are cheap and absolutely OK in the beginning for your needs.
In a British outdoor forum people focus on plastic material because that's more comfortable to use in a rainy country. But for you cotton, linen and leather equipment surely will work as well if not even much better. It usually lasts much longer, is rather spark resistant and if it touches your body it sucks sweat better away from you. And it's often cheaper too if we talk about military surplus equipment.
Get a first improvised equipment together and focus on the skills.
You need approximately this here:
No Nonsense Kit List
Bomb proof, Low Budget
BW mountain troop rucksack, Cordura
BW folding mat
BW poncho
Edelrid multicord 3 mm
BA bivvy bag
BW sleeping bag Tropen
US rubber bag, Nylon (ALICE liner)
BW padded jacket
KL draw string bag (for poncho Liner)
BW tropical briefs
BW tropical T-shirt
Falke TK1 socks
Swimming briefs
BW washbag
BA soap tin WW2
Aleppo soap
Fuchs travel toothbrush
Wilkinson's Pronto razor
Ajona tooth creme
BW triangular bandana
EI shaving mirror
Toilet paper
DC4 sharpening tool
BW Esbit stove
BW cuttlery kit
Bic lighter orange
KL draw string bag (for poncho Liner)
BW mess kit containing food
BW strap for it
On the man:
BW boots by Reck
Falke TK1 socks
ÖBH Trousers KAZ 75
BW tropical briefs
BW trouser belt, olive
Morakniv Garberg, stainless
Victorinox Climber with lanyard
BW handkerchief
House keys with lanyard
Noaks bag A4 with hiking map
BW field shirt, olive
BW tropical T-shirt
Wallet
Bic lighter red
Petzl e+lite
Suunto M-9 compass
ÖBH Feldbluse KAZ 02
US belt ALICE
US canteen pouch ALICE (2×)
US mug
US canteen (2×)
BW - German army, ÖBH - Austrian army, KL - Dutch army, BA - British army,
US - American army, EI - Italian army