#05AB1E , 14 bytes

Uses 0-indexed output. Prime functions in osabie are very inefficient. Code:

[NØJD1å#]1.Oð¢

Explanation:

[ ] # Infinite loop...
 N # Get the iteration value
 Ø # Get the nth prime
 J # Join the stack
 D # Duplicate this value
 1å# # If the input is in this string, break out of the loop
 1.O # Overlap function (due to a bug, I couldn't use the index command)
 ð¢ # Count spaces and implicitly print

Uses the CP-1252 encoding. Try it online!.

05AB1E , 14 bytes

Uses 0-indexed output. Prime functions in osabie are very inefficient. Code:

[NØJD1å#]1.Oð¢

Explanation:

[ ] # Infinite loop...
 N # Get the iteration value
 Ø # Get the nth prime
 J # Join the stack
 D # Duplicate this value
 1å# # If the input is in this string, break out of the loop
 1.O # Overlap function (due to a bug, I couldn't use the index command)
 ð¢ # Count spaces and implicitly print

Uses the CP-1252 encoding. Try it online!.

#05AB1E, 14 bytes

Uses 0-indexed output. Prime functions in osabie are very inefficient. Code:

[NØJD1å#]1.Oð¢

Uses the CP-1252 encoding. Try it online!.

#05AB1E, 14 bytes

Uses 0-indexed output. Prime functions in osabie are very inefficient. Code:

[NØJD1å#]1.Oð¢

Explanation:

[ ] # Infinite loop...
 N # Get the iteration value
 Ø # Get the nth prime
 J # Join the stack
 D # Duplicate this value
 1å# # If the input is in this string, break out of the loop
 1.O # Overlap function (due to a bug, I couldn't use the index command)
 ð¢ # Count spaces and implicitly print

Uses the CP-1252 encoding. Try it online!.

#05AB1E, 14 bytes

Prime functions in osabie are very inefficient. Code:

[NØJD1å#]1.Oð¢

Uses the CP-1252 encoding. Try it online!.

#05AB1E, 14 bytes

Uses 0-indexed output. Prime functions in osabie are very inefficient. Code:

[NØJD1å#]1.Oð¢

Uses the CP-1252 encoding. Try it online!.