Installation of Postgres 10.0 and running application with HAwithout postgres user at OS

Hi , 

I am using RHEL to install Postgres 10 and setting up replication . But in my OS no postgres user exists . Installed it with sudo access . Can I run the postgres DB with all it's utility (like psql, vaccumdb , pg_rewind , initdb etc.) along with Master slave replication, archival process without postgres user. 

If it can be done , do I need to follow any extra step to the os user apart from postgres ?

Is there any way to skip postgres os user ?

Thanks , 
Soumitra