Can I swap my front 2x chainring on my MTB to a ~46T chainring?
It is possible to do a 2x to 1x conversion but as stated in other answers you generally need to do something to keep the chain on the chainring. Generally a narrow-wide chainring is used on 1x setups to retain the chain. Leaving the derailleur in can also accomplish this.
Re-using a double crank with a single biases the chainring to one side, ending up with unavoidable cross chaining. I’ve heard special rings that offset the teeth are available.
If you want a chainring larger than your current one you may run into chainring-chainstay clearance issues, especially on a bike designed for small rings such as yours. A significantly larger ring (46 instead of 36 in your case) is very likely to have clearance issues.