Error starting userland proxy: listen tcp0.0.0.0:3306: bind: address already in use

I had the same problem and

sudo netstat -nlpt |grep 3306

showed me the PID and which service it was started by (mysgld). Whenever I tried to kill the PID then it was started again. But the problem was fixed when I stopped the service by

sudo service mysql stop

Notice that you will have to use mysql and not mysqld.

I hope that this will do it for you - I was able to run docker-compose up without any problems

Probably you have already a MySQL service running in port 3306. You should close it first.
Then try to end docker-compose down and restart it with docker-compose up.
Remember also to change the permissions after you add a file in your project (like dartisan make:auth) with dpermit

UPDATE:since you have changed the port to "8084" you should go to localhost:8084
If you see the apache default then you probably are browsing another server since dockervel is build upon nginx.
You have also probably have some gaps on Docker. Don't mix your local storage with docker storage. /var/www in a container is different than your local /var/www. in docker-compose.yml you mount the local ~/dockervel/www to containers /var/www.
I would suggest that you start all over again and revert the changes you've made to your apache server. Shut it down, you don't need it. Dockervel will provide you with an NginX server in a container.

Try to kill all the processes using the port 3306:

sudo kill `sudo lsof -t -i:3306`

Then, run your docker containers:

sudo docker-compose up