Building a FPV quad - rx question

[Brojon]

Absolute total n00b here trying to learn the ropes.
On the advice of many I bought a Q X7 RC - nice radio and plays well with Windows 10 for Liftoff and other sims.
The question of which receiver to use in my FPV build is sure causing me some angst - mostly because I don't even know enough to be dangerous.
So I figure I need about 6-8 channels - 4 for standard functions, 1 for arming, 1 for failsafe, 1 for buzzer, 1 for mode change (leveling/acro)
I'd also like to have battery telemetry but the whole subject of telemetry is seemingly shrouded in secrecy Near as I can cipher it means the RX can talk back to the RC - but about what?
It appears the FrSky X4RSB has 3 "normal" channels but 16 sBus? What does that mean exactly?
I found it in a search for RX that can monitor the LiPO voltage - is there another way or a better RX?
Thx!!

[Daedalus66]

First, understand your transmitter. No need to guess. Nothing is secret. Read one of the three excellent manuals on the QX7:
viewtopic.php?f=45&t=10576

Second, decide on the kinds of machine you want to fly and read up on them. Read about flight controllers and choose one of the popular ones. There’s lots of advice available on line.

Presumably you will want an FC that uses SBus.

Third, only when you’ve understood all this will it be time to worry about receivers and telemetry. You will probably want to use a small receiver with SBus such as the X4R. That will drive the FC and provide battery voltage and RSSI telemetry. These are the usual priorities, but there are other kinds of data that could be sent, such as GPS.