To buy BitCanna (BCNA) on Osmosis DEX, first buy Cosmos (ATOM) coin, then deposit it to your Keplr (Browser wallet) or Cosmostation wallet (Google Play, AppStore, APKCombo downloader), swap ATOM to BCNA on Osmosis DEX. The sequential guides are listed below, just swap ATOM to BCNA following the last guide, there is swap to OSMO as example there. You can use the Cosmostation wallet the same way as Keplr in the sequential guides below.
To stake BCNA, you need to install Cosmostation wallet (Google Play, AppStore, APKCombo downloader), deposit one with BCNA coins and delegate it to a validator using the wallet. How to do this, please see in the guide below.