Hey,
the pipe is missing in the command block:
echo "deb http://repo.mongodb.org/apt/debian buster/mongodb-org/5.x main"
sudo tee /etc/apt/sources.list.d/mongodb-org-5.x.list
correct is:
echo "deb http://repo.mongodb.org/apt/debian buster/mongodb-org/5.x main" | sudo tee /etc/apt/sources.list.d/mongodb-org-5.x.list
and here:
sudo systemctl --type=service --state=active
grep mongod
correct is:
sudo systemctl --type=service --state=active | grep mongod
and here:
echo "deb https://artifacts.elastic.co/packages/oss-7.x/apt stable main"
sudo tee -a /etc/apt/sources.list.d/elastic-7.x.list
corrct is:
echo "deb https://artifacts.elastic.co/packages/oss-7.x/apt stable main" | sudo tee -a /etc/apt/sources.list.d/elastic-7.x.list
H077E