Macbook air won’t connect to ipad or iphone via bluetooth

Bluetooth pairing an iPhone to an iPad or to a computer (Apple or non-Apple) is not supported.

An iPhone will not pair via Bluetooth to a computer (Mac or Windows) or an iPad except for personal hotspot and then only if your cellular plan supports it. See the following for more information: Bluetooth: Why can't I pair my iPhone or … - Apple Community

If you are attempting to use Handoff/Continuity or AirDrop, that does involve Bluetooth but the devices are NOT paired; Bluetooth just needs to be on and the devices in range of each other. The following may help with Handoff/Continuity issues: Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support

Also see Share files between your Mac and Bluetooth devices - Apple Support

ArgyleMO wrote:

So how have I done it before? I have an app on my MacBook that allows me to use its keyboard to type on my iPad?  I used to connect MacBook to ipad via Bluetooth and then I could open the 1keyboard app and use the keyboard on the MacBook to type on ipad. 

I don't know. May have something to do with the app. Mac's and iPads/iPhones not pairing isn't new.

I checked the App Store and it appears that the 1Password app hasn't been updated for 7 years so there may be something related to that.