@jimmiduke007
Then i am going to bet that the wifi connection is the main culprit at this time.
Wifi connections are great however at any given time something can cause a decrease of connection stability, this can be anything from a car passing by to a microwave turning or something like that.
For regular internet use (watching video, browsing the web etc) this is not a major issue because even a 10’s of seconds long interruption is not a big issue because of data buffering.
However with something like an online game like sea of thieves that needs a constant data stream it will be noticeable
I do have to add, lag spikes are sadly not uncommon in the game but usually not so extreme that they submerge your ship