Is there something I can seal the seams with for peel/stick tile?

Yes. You can use a vinyl floor seam sealing kit. Here's a link:

https://www.hunker.com/12616067/can-you-seal-peel-and-stick-tiles

Clean the tiles and seams with a rag moistened with soapy water. Then squeeze a thin line of seam sealer, per the manufacturer's directions, along the seam lines and wipe away the excess sealer on the tiles with a clean rag or sponge.

Seam sealer is what people use to seal or join togather the seams in their sheet vinyl etc.

Seam sealer for vinyl floors

https://www.homedepot.com/p/Roberts-8-oz-Vinyl-Seam-Sealer-for-Sheet-Flooring-7500-8/307565677

Yes, you can use a seam sealing product available at most hardware stores. Just follow directions and you should be good. I will say that I've had issues in bathrooms with this type tile, especially if there is any dampness at all. So I think it's a good idea to seal them. I also use extra adhesive but it appears your job is completed so that's not an option.

Armstrong makes a good product:

https://www.lowes.com/pd/Armstrong-Flooring-S-761-Seam-Sealer-Sheet-Vinyl-Flooring-Adhesive-8-oz/999978478

You can fix vinyl plank flooring gaps by using a floor gap fixer, epoxy resin, grout, or leftover vinyl pieces or wood. If you want the most straightforward solution with the least mess, use floor gap fixer, although this may be more time-consuming. For smaller holes/gaps, use epoxy resin or grout.

Hi Teresa, it's a pretty easy fix. Just ask your local hardware store or the place where your bought the tiles for a vinyl floor seam sealer and follow the instructions on the packaging

LIft and use gorilla glue on edges.

You shouldn’t have to seal the seams they should be fine like that

Here's a video that shows how to seal your floor seams with a sealing kit!

https://www.youtube.com/watch?v=JQU3hsY10-M

It would depend on the type of tile you use. I’ve seen some that you can use grout.