if your filamenty path is good you can just heat up the hotend and pull the filament out and then push the new one in.
If you've got a chamber build up anywhere, then push a little through before pulling it out.

Colour wise - different colours do print at different temps.
Black will probably need a slightly higher temp than red and won't flow quite as easily so usually needs tobe printed at a slower speed. Though that depends how fast you've been printing the red.

I generally print all pla at 210c, I'll up that to 215 if printing at 150mm/s and drop it to 200 if printing at 40-50mm/s
Black tends to be slightly more viscous than other colours, so keep your travel movement close to your print speed.

That said - different brands print differently anyway.
So initially keep the same settings, and then adjust if your have any issues :-)