Bluetooth not available

What do you mean by "not available"? Are you not able to turn it on? This could be a variety of things, worst case would be a defective bluetooth module. Did you already try doing a PRAM reset?

 

First, it would sure help if you told us what model MBPro you have and what year it was made -- and what version of the OS you're using.

Suggestions and thoughts:

Open System Information (utilities folder) and click "Bluetooth" (upper left).
What does it tell you on the right?

It should show -something there-.

If it just gives you something like "Bluetooth not available", it could be either:
- hardware (not sure if the MBPro has a removable BT module or not)
OR
- software (drivers for BT not loading at bootup, or perhaps they're missing).

Poki's suggestion about a PRAM reset is a good one.

 

Since it happened after updating to High Sierra, doing a fresh install might be a good option (don't forget to backup your data!).

 

After you've created a full backup using Time Machine or something similar on an external hard drive, hold cmd + r while booting. Choose the hard disk utility there and format your hard drive. After that, choose reinstall macOS from the menu.

Apple explains it here in more detail:

https://support.apple.com/HT201314