few things you can do right now in Belgium
Change your electricity supplier : https://monelectriciteverte.be
Change your email address : https://mail.lilo.org
Change your savings bank account : https://www.triodos.be
Getting a GoodPay card (master card) : https://www.newb.coop/fr/home, http://goodpay.coop/documents/GoodPay_Manual_FR_NewB.pdf
Change your search engine : https://www.lilo.org/fr/, https://www.ecosia.org
Change your mobile operator and become a cooperator at Neibo : https://www.neibo.be
ACT here : https://www.citizensforclimate.be/fr
Interactive map : https://maps.dewey.be
Get a STOP PUB : https://www.ibpt.be/fr/consommateurs/faq/71-je-ne-souhaite-plus-recevoir-de-publicite-non-adressee-comment-le-faire-savoir
Boycott : https://www.i-boycott.org