I get a lot of FallingSand where I need FallingBlock. Is there a way to get that to work easily?
Solution 1:
There is no easy way. There are some 1.12→1.13 command converters online that can do this for you, otherwise you need to re-create the commands. For that, you need to understand them, I recommend the Minecraft wiki.
Here is an example for summoning a falling stone block:
/summon falling_block ~ ~ ~ {Time:1,BlockState:{Name:"stone"}}