Upgrade from PostgreSQL 11 to 14 in RHEL dependency errors

Question

I use RHEL 7.5 to host postgresql11 and I want to upgrade the existing postgresql to 14.

I initialized the DB and proceeded to check the upgrade.

While using the pg_upgrade --check it tells me that pg_trgm is missing along with tablefunc and postgres_fdw.

Ok so I google that, it seems that postgresql14-contrib needs to be installed. When I try to install postgresql14-contrib I get the error that it requires libpython3.6m.so.1.0()(64bit). So it seems that nothing in my repolist provides this and I downloaded the .rpm manually to install it but then I get more dependency problems that yum is unable to resolve. Is there a way to point yum to find all the dependencies it needs?

NOTE:The VM that runs RHEL 7.5 is behind a firewall

I tried copying the pg_trgm.so,tablefunc.so and postgres_fdw.so from the older version as a workaround but I get errors when I run the pg_upgrade --check.

I also tried using yum search python3. It returned a lot of results but I am not sure which version to install.

Thanks for your time reading this and I am sorry if the answer is right in my face but its the first time that I am dealing with RHEL and yum, and I already spent about 10 hours trying to solve this by myself.