Should be pretty straightforward.

SRAM 1x setups use a narrow/wide chain, so you need to make sure whatever chainring you buy is narrow/wide. There are some different bolt diameters and patterns for different cranks, so you may need to measure your current setup to find out what it runs. It might be marked on your current chainring. (My setup uses a 110 BCD 5-bolt, for example)

You haven't told us how much smaller you're planning to go, so hard to say if you'll need to shorten your chain or not. The only tools you'll need are an allen key. You will probably want to remove the chain, but I suppose it might be possible to do this without even doing that. Literally just unscrew the old chain ring and bolt the new one on.

You can get an idea of how much a new chainring will change your gearing by plugging info into a bike gearing calculator like this:
https://www.bikecalc.com/speed_at_cadence