minecraft command conversion from 1.9 to 1.14 help?

Solution 1:

For the repeating command block, use:

execute if block <x> <y> <z> lever[powered=true]

and use these two in the two chain command blocks:

execute at @e[name=GREENLIGHT] run particle minecraft:dust 0 1 0 1 ~ ~ ~ 0 0 0 0.05 100

execute at @e[name=REDLIGHT] run particle minecraft:dust 1 0 0 1 ~ ~ ~ 0 0 0 0.05 100

in case you want to customize the color ot size, here is the syntax for the dust particle: /particle dust <r> <g> <b> <size> <x> <y> <z> <width> <height> <length> <speed> <amount> (force|normal) (selector) with the (force|normal) and (selector) being optional so I didn't include them in the commands.

to summon the armor stand, use:

/summon armor_stand ~ ~ ~ {NoGravity:1,Marker:1,Invulnerable:1,CustomName:"\"GREENLIGHT\""}

make sure your chain command blocks are conditional for the lever detection to work properly.