Yes, this is the perfect time to start giving nutrients. The soil got enough nutrients for about 6 weeks.
You need to give a blooming nutrient with a higher ratio on phosphorus (P) and potassium (K).
You can start giving a bloom basic nutrient. This contains all the nutrients necessary for during flowering.
And you can give a PK product like PK-Booster or PK 13/14
Always start with small steps. Around 25% from the adviced amount by the fertilizer company. You can always add more but can not get it out once given.
And always up with 25% or down with 25% Plants do not like huge changes thats why the small steps.
Enjoy your grow!