If I missed quarterly tax payments for the current year, what should I do.

Making the payments as soon as possible will decrease any penalty. 

you will have a penalty for Q1 but you can minimize it by paying it ASAP to stop the penalty from accruing further.  The calculation is quarterly and cumulative i.e. you need to pay 25% by Q1, 50% by Q2, 75% by Q3, 100% by Q4.

also check the ES amounts if you are using the amounts generated on the vouchers by TT (but pay electronically at irs.gov if able, you don't need checks and vouchers), those amounts by default assume you will pay 100% of your 2024 tax (110% if AGI > 150k) and that your withholding in 2025 is the same as 2024, the difference is the ES amount divided into 4 quarters.  Alternatively you can pay 90% of your 2025 tax that is smaller, but you have to estimate that.  You can also increase withholding for the rest of the year if you have W2 income etc which is always considered "timely" even if it wasn't withheld earlier in the year, tho you only have about 6 months left to make up the tax that way, but any increase in withholding will reduce the amount you need to pay in estimated tax (and in turn reduce the final penalty for Q1).