RF transmitter steps explained in detail if you dont mind:(

Hi guys Big time noob here,
I find it all very hard to do.
So here iam again with a question for a tutorial.
SO problem is here… i bought a RF transmitter and receiver. Bought are connected to mine PI
Now i was following a tutorial for python3 instal, that dindt work when i recieve.py i get cant open the file., So i was this far, and figured i got 2 scripts i need to import, HOW in the hell do i do that?? i have really no idea. Can someone help me from here?
I know about Configuration.YAML

There are 2 scripts recive and send, and there a build like the need in configuration.yaml. But when i copy paste and put in the Yamlint.com it gives a error that (<unknown>): could not find expected ‘:’ while scanning a simple key at line 67 column 1