"what skills exactly are RF skills?"
In short, something you acquire with " Blood
,sweat and tears
over a long period of time.
I don't intend to discourage you,but you should know what you are facing.
If you have a "digital background",
there would be a long way for you to enter the "RF world" and survive...
"what equipment I need ?"
For starters for that 98Mhz osc. analog circuit:
1)100MHz (preferably 150MHz) scop and probe(s)
2)100Mhz (preferably 150MHz) "sensitive frequency counter".
3)Very "clean" power supply.
4)RF quality Capacitor/Inductors "sets".
5)Bare PCB for "dead-bug" assembly.