Move from hdd to ssd
Im building a system and I don't have an ssd right now because it wasn't in my budget. Is it possible to move important data on my hdd to an ssd when I get one, such as my os, certain games, etc.
Yes, it's possible.
You just have to partition your HDD accordingly.
Make one partition for OS (not larger than SSD, you're planning to get) and
another partition for your data.
When you get your SSD, you just clone bootloader and OS partitions to SSD,
change BIOS settings accordingly and fix bootloader.