I was doing a little digging last night and I found this sermon. The person who responded to me said that round earth was biblical. He uses Isaiah 40:22, which refers to earth as a circle to say that the earth is a globe. Since when is a circle a globe? I highly recommend watching the sermon I posted above. It has many Bible verses in it that support a flat earth. A few Bible verses that convinced me are as follows.
Isaiah 38:8 - "Behold, I will make the shadow cast by the declining sun on the dial of Ahaz turn back ten steps.” So the sun turned back on the dial the ten steps by which it had declined." This verse says that God literally made the sun move backwards. He didn't make the earth spin the opposite way, He moved the sun backwards.
Psalm 104:5 - "He set the earth on its foundations, so that it should never be moved." This verse is saying that the earth has a foundation and it does not move. This goes against everything mainstream science tells us about earth being a spinning globe.
Job 37:18 - "Can you, like him, spread out the skies, hard as a cast metal mirror?" This verse says that the sky is as hard as a cast metal mirror. This fits the Bible's continuity of a solid firmament/vault that divides waters from waters.
I'm still not 100% in believing the earth is not a globe, but I do believe that the Bible cosmology supports earth as a fixed, motionless, and flat plane. A common argument against this is that everybody back in Bible times believed earth was flat, so that might have influenced how they thought the earth looked. But, It's pretty hard to believe that God would give prophets incorrect visions of what the earth looks like. I'm going to keep doing research, but I do trust the Bible, which has a track record of telling the truth, over the teachings of man, which have a track record of lies. The video I linked above uses these Bible verses and more to explain them a lot better than I can.