As a new engineer (engineer #2) at a startup decades ago, I was asked to teach the new incoming engineers about the company product.. Next week.
Forcing myself into the mindset that I had to explain it to others in a meaningful and comprehensive way - AND to be prepared to answer questions - I learned and understood the product in record time. It wasn't perfect, but holy moly was I motivated to know it well enough to explain it.
There are usually some good deals on used gear and things suitable for selfhosting if you want to go that route. I was able to build a 3 node cluster with lots of CPU/RAM (~100 vCPU/256G RAM) and storage (30+TB) on systems with redundant power supplies made for datacenters for under $500.
Upside: one time cost and usually cheaper than cloud-hosting costs.
Downside: power consumption (energy bill) increase unless you go with something like a Pi cluster, and you need to setup security well if you intend to expose any services to the Internet.
I have a fairly close-knit team at work and in 2022 we challenged each other to a monthly exercise. February was push-ups, March - standing squats, etc. It was just do what you can, but do it.
I started this as an evening ritual, then would shower and go to bed. I would add reps to the exercise and build on it, but each month I would continue to do the prior month's exercise and build on the routine. Before too long I had a 15-20 minute workout without owning any equipment or gym membership.
I had a few times where I just couldn't get to the routine. I noticed that I would feel worse (weaker, less rested in the morning) if I didn't get the routine in before bed.
In 2023, we don't really do that anymore for various reasons, but I still try to do the routine 3-4 times per week. If I go too long between workouts, I find its sometimes necessary to lower the number of reps and build back up.
The key for me is to just do it and be consistent about it (it really is only about 15 minutes so I find it hard to make excuses to skip it). I'm at the age where there is a lot of benefit to consistently moving your muscles and stretching...
Forcing myself into the mindset that I had to explain it to others in a meaningful and comprehensive way - AND to be prepared to answer questions - I learned and understood the product in record time. It wasn't perfect, but holy moly was I motivated to know it well enough to explain it.