There's a lot to learn for Mixing... Basic Mixing is usually knowing how to fade in & out sounds using the Faders, & knowing what Mixing Tracks are assigned to what Sounds.. More difficult mixing comes with Equalizing & Automations, or at least for me. Also, for the tempo, the BPM is what controls the Tempo also, using a Metronome can help with staying on-tempo, but it can get annoying real fast. (Or at least in my case...) Some Plug-Ins (Like Soundpaint & Omnisphere) can match their Sounds inside of the Plug-In to match the BPM inside the DAW you're using. Finally, usually Online, doing Searches and/or watching YouTube Toutorials is a great way to figure things out to do with Mixing! (That's what I did when I was new to Mixing too!) Glad to be of help. Hope you have good luck finding out what you'd like to learn!