How do I seal my enclosed porch water is coming in?

Clear caulking would be the easiest way.

The better answer is to remove the water. If you allow it to stay where it is it can damage your foundation. Now, the best way to remove the water is with a ‘French Drain’. These yield excellent results, but they are very labor intensive, and I they are not done right, they will not work.

Where is the water coming from? Along the ground? From the eaves? Around the windows?

Exterior caulking Stain floor, do not paint. Google it. Also a nice outdoor rug and decor as u would do on a patio. Some old white wicker with a thrift store find coffee table chalk painted. Even some thrift store old frames chalk painted with no pictures in them.

It will look great.

Perhaps your roof needs attention, as Susan suggested.

If the porch is under a deck, you need to install under-decking with gutters. They work great

https://www.familyhandyman.com/decks/building-a-deck/under-deck-roof/view-all/

Where is water coming from?

Get the expanding sealer that plumbers use. It comes in aresol cans. When the spray comes out, it expands to a few inches in diameter. The sealer will keep out all moisture from the places you seal. Spray inside or outside of your porch, but I would choose inside, on all outside seams. If you have any loose or missing boards, fix those and seal them. Spray the seams in other places, too, such as where the porch is connected to the house at the walls, roof and floor. The yellow foam can be painted or camouflaged, but it will keep the moisture out of your porch. Exceptions would be if the roof has a leak or if the floor of your porch is lower than the ground outside or in a runoff area, or if windows are not properly sealed. Real room are similarly sealed, but the drywall or paneling usually hides it. You could rewall the inside of your porch room, too. Best wishes ☺️