My Samsung phone has a setting that allows it to use 4g + Wi-Fi to increase speed in some cases. Can the same be done on a MacBook with Bluetooth network + Wi-Fi?
If I understand your question correctly, the example you're using about your Samsung phone having a setting that allows it to use 4g + Wi-Fi to increase speed in certain circumstance is the same option iPhone users have (Settings > Mobile > Wi-Fi Assist). It's primarily to allow the use of mobile data when Wi-Fi connectivity is poor.
The key thing about this option is that in both cases (Samsung / iPhone) we're talking about a data connection to the internet (i.e. 4g and WiFi). What I mean is that both 4g and Wi-Fi can connect independently to the internet.
With regard to your question though, you're talking about Bluetooth and Wi-Fi. The thing is that Bluetooth in and of itself does not have a data connection to the internet - so it's not like it can assist to increase speed because it isn't connected in the first place.
Devices (Macs and iPhones included) can share their already connected internet connection via Bluetooth to other devices, but no you can't use both Wi-Fi and Bluetooth to increase an existing internet connection.
If I've misunderstood your question, please let me know.