Yes, investments are really important. Everyone invests in one way or another. Because investments are like sowing and we all sow, whether it's in our finances, health, knowledge, relationships, etc. Investing at the right time is a win-win. But it's also never too late to invest. Investments come from money saved, making savings just as important as investments. You barely can invest what you haven't saved up or worked for.
So, just like OP, I also urge us all to save and invest in ourselves, we don't have to wait until there's barely any fruit to reap before we sow.
Everything comes if there is a strong will and opportunity. The opportunity here is when there is a good opportunity for us who certainly have more income than we can save, that is where our opportunity to invest first comes.
When it comes to time, there is no limit, but from my experience it is best to start when we are young, by doing this it will really help us when we have a family and we will naturally get used to prioritizing things that are important, urgent or just ordinary needs. So, we just have to do it with our beloved wife.