Most if not all the websites use a secure connection which browsers show as a little lock on the screen to indicate the connection is secure.
If you were really worried then the simple payment with a check reveals all the information needed for someone to get money out of a bank. At times you can get so worried you may want to buy a mattress.
https://www.cnet.com/news/say-good-bye-to-that-green-secure-lock-on-google-chrome/ notes that Chrome has changed to warn of unsecured web connections.
We are forced to get Hughes Net. Even a dedicated hotspot will not give us internet. We just need "some" internet for simple research and paying some bills.
Question... Is it safe to pay bills using satellite internet? My wife is worried that someone can snatch our information out of the air when using Cell towers or Satellite... Keep in mind that we are far enough out that there is not any other service providers in our area... Which should tell you how few people there are...