I'm gonna tell you something people often forget: shoe price matters quite a bit if you've got sensitive feet or a particular gait. Like if you tend to overpronate or you have flat feet, a €50 model can wreck your ankles after a few km. But if you've got "normal" feet and you're really just starting out, yeah it's totally doable.
The right approach is not to get hung up on premium brands. Decathlon honestly isn't bad for the price, their stuff holds up. The thing that actually changes between a €70 shoe and a €150-180 one is durability and comfort over long distances, not really the base quality. You're not gonna sprain your ankle in Decathlon gear if you're careful at first.
Just try to buy in a store so you can test them, not straight online. Walk around in them, feel if they rub, if the cushioning feels right. And honestly start out gradually with distances - it's less the equipment that kills beginners than wanting to do 15km all at once. If after two months you see your feet are suffering or you want to get serious about it, then you can invest in something better. But it's not necessary right from the start.