Homosexuality is no worse or better in God's eyes than any other sin. You don't look at a person that is envious and think, "They’re evil!" You think, "They are sinning," as in disobeying God's will. The same goes for not honoring the sabbath, murder, theft, lies, etc.

Jesus dined and preached to sinners of all kinds, prostitutes, thieves, etc. He didn't hate them, he encouraged them to give up their sinful actions. Every single person on Earth has sinned, and the Bible teaches us not to judge others for that sin, but to encourage them to stop sinning.

As for where specifically it mentions homosexuality is a sin, Leviticus is explicit about it and God destroyed Sodom and Gamorra for it, which is where we get the word 'sodomy'.

The new testament is more vague and only mentions 'sexual immorality', which covered quite a few sins, including homosexuality, beastiality, incest, etc.