I can give you some tricks with compressing drums or sounds. When compressing a kick snare or hat or the whole drum thing together. Use a hard Knee on drum tracks treshold depends on how loud the output volume of the drum is. Attack= when the compressor wil start working afther the threshold point has been reached. For a kick and snare for example you would want a compressor to react fast right so attack is lower number lets say 30-50 maybe even 20. Release how long the compressor wil keep working afther the volume gos below the threshold. Release is ussually short aswell with drums. Ratio for drums keep it @ 1:5 or 2. How wil it sound if you overcompress.. You will prety much start hearing a kinda suck effect yeah sounds weird but its very identical. Compressor wil give your drums more punch and willl make your drums sound fatter.
Pads/Synths: Use Soft knee on the compressor. Threshold depends on the output volume of the sound. Attack ussually longer than with kicks for example if i have a pad i will ussually start of with 50 and maybe go up to 80-100. For release also longer times ussually maybe 300 to 500 . Threshold for pads synths stuff you can easily put ratio @ 3:1 or 4:1 but also 1.5:1 and 2:1 are commen aswell.
Another tip i learned from sound design. If the compressor compresses more than 3 DB you will start using the compressor more as an effect if you compress more than 3 DB it wil alter your sound pretty drastically from there off. Use the compressor wisely.. It can make/break your beat. Use your ears try to hear what the compressor does. It's very hard to notice as a beginner beatmaker but when you get more experience you wil pretty much do it by listening to the sound. Good luck and stay creative.