Uppercase first sentence in every post

Brand new to this community but been tinkering with WordPress for years.

I would like to edit my website’s functions.php file to be able to automatically do a task I have to do manually each day.

Basically, everyday I write a discussion with 5-20 paragraphs. At the beginning of each paragraph, I always lead with “PARAGRAPH TITLE HERE…” (without the quotes), so the discussion looks like this:

WHO LET THE DOGS OUT… Paragraph text here describing who actually let the dogs out. I wonder who let the dogs out. Long paragraph text here.

I AM EATING A RAISIN… Yes, raisins are supposedly good for you. Lots of sugar, but good. Raisins are made from grapes.

Basically, I want the functions.php file to make the words before the three dots uppercase in every post I do. What is the most effective way for me to accomplish this? Thank you!