Completely new to investing, how much to invest and where

Hi guys, I’m currently 25 yo, and have about 22k in savings. I just took a pay cut, so can only save about 700 per month after deducting all my expenses. Initially I wanted to aggressively save but am thinking of starting to invest for my retirement planning. If I’m looking to get married at 30 and have at least 50k, what do you think is a good amount to invest and what amount to save? Any tips on how to reach this short term without compromising on my long term goal? Thanks in advance!