Least learning curve to (semi) auto config new sites switches and firewall from standard/template?

So my shop brings on a few new sites/clients a year and they all follow our standard setup for a standardized set of vlans, tunnel back to HQ network, and some configs for things like multicast/igmp etc etc.

We run Ruckus ICX switches and are using Palo Alto firewalls.

What automation tools have the least learning curve to be able to say

1. Define new customer site is 10.xxx.0.0/16

2. Plug in new core switch. Have it grab a core switch config for the 10.xxx site scheme.

3. Plug in second core switch. Have it grab appropriate config with next IP in the scheme.

4. Plug in a new access switch. Have it grab a access switch config for 10.xxx site scheme. And get an appropriate IP in the scheme.

5. Repeat for other access switches.

6. Plug in new firewall. Have it grab firewall config and maybe all I do is put in the wan provider details.

Etc...

I always hear Ansible or python this or that but have yet to find a solid tutorial tgat does a lot of hand holding. I need the hand holding.

Any favorites out there? TIA