My Rocket.chat setup is not working on ubuntu server

My Rocket.chat(https://rocket.chat/docs/) setup is not working on ubuntu server as rocket.chat has already mentioned in their docs
documentation that the minimum requirement (https://rocket.chat/docs/installation/minimum-requirements/) is
Single core (2 GHz)
1 GB RAM
30 GB of SSD

my server specification is

Node 12.14.0
Meteor 1.9.2
Rocket chat 2.4.2
Platform: linux
MongoDB v4.0.16
1 GB RAM and 1 CPU 

i don’t know what is happening , is it the mongodb who is utilising the server memory?
can anyone help me out for this

thanks