As for mining/staking, most of the guides are outdated due to the many updates.
If you want to try, you can either use the standalone server or update the heatledger files in the wallet to use server v0.9.21.
I prefer staking through the wallet as its easier to set up. Once you got the correct server version in the wallet, you need to edit the heat-default.properties or make a heat.properties file and set this heat.apiKeyDisabled=true
Then you can just click start server, wait until its updated and click start mining.
At the moment the staking rewards is 0 until the current issues have been fixed, so you wouldnt gain anything from mining.