Help needed. Bluetooth's been swtched off

I did an Avast smart scan the other day & it came up I was vunarable to be connected to by other people. It said to disconnect something to stop this happening & it wouldn’t affect my wi-fi, so I chose to disconnect & thought nothing of it.
However, I use a stand alone speaker connected by bluetooth as the latops speaker is useless & I noticed I wasn’t getting any sound thru it. I went to control panel/device manager & bluetooth has totally gone. In search for bluetooth I can see what devices were connected but the “connect” part isn’t highlighted.
I’ve tried windows help to re-install bluetooth drivers but I need bluetooth to be seen on divice manager & since it’s not there, I can’t install the drivers.
What I need is to go back to the page where I was told to disconnect stuff & re-connect the items that are now hidden from me.
Can someone Please help me as I’m going around in circles here.

What operating system? Do you use System Restore?