Design a relay driver from TTL input with common parts
It seems you want to drive a solenoid valve using common parts and control it with TTL input such Arduino device?
The common approach for DIY level, is to use NPN transistor (BD681G On Semi could work) to drive relay that then switches on the solenoid valve. Note fly-back diodes are required across inductive loads when switching to avoid device failure (i.e. relay coil and solenoid coil). Example in link below:
https://web.cecs.pdx.edu/~eas199/B/howto/fishtank/wiring/solenoid_wiring.html
The power rating for model SC-N14 DC12V version indicates holding power. When first powered on the in-rush current for relay can be about 2-3 times, select components accordingly. For DC solenoid valves there's no large in-rush current but for AC there is (edited).
https://www.ia.omron.com/support/faq/answer/36/faq02165/index.html
EDIT:
An example circuit would be using mosfet with low Rds resistance. Flyback diode selected to withstand max current from solenoid. Pull-down resistor at gate of fet to have default state.
The NPN BD681G cannot be used reliably in this configuration as the on resistance would cause voltage to be about 1.5volts less than 12V (large Ron resistance), voltage divider would also be needed to avoid exceeding Vbe_max.