Does studying Tantra go against religious beliefs?

Tantra is not about worshiping another person.
It is partly about recognizing divinity in another, something I think is compatible with Christianity.
Some call it the “yoga of sex”, but most serious practitioners/instructors believe it’s more about love, and less about sex. So if you keep that in mind, you’ll be fine.

if you’ve ever had Tantric sex, you’d understand it better ;-p

Any religion that does not allow you to study other religions is a religion that is afraid of other religions.

Tantra is a Hindu sect that engages in various sex acts in the temples. I think you might be missing something here.

Tantra is a part of Bon (a Tibetan religion),Jain ,Hindu and Buddhist belief systems and other religious traditions . It is not part of Christianity or Judaism, it would be antithetical to them , i study many other religions than my own but i only practice my religion

Tantra and Neotantra are 2 different things but Westerners think they are the same. Tantra is an orientation toward religion that is highly experiential and also highly ritualistic and is an integral part of Hinduism and Buddhism and Yoga. Indeed common cultural Hinduism and Mahayana Buddhism–which includes Tibetan Buddhism–are Tantric. This doesn’t mean that their practices involve sex magic. Sex magic or “sacred sexuality” is part of some fringe, esoteric spiritual groups within Hinduism and Buddhism and Yoga traditions. This became sensationalized in the West and took the form of Neotantra and also influenced Western occultism.
Ideally in Tantric practices involving sexuality, sexual energy is equated with spiritual energy to cause a different kind of experience than what one ordinarily experiences in the mundane sex act. In some schools of Tantric sex, the act is thought of as devotion and the partner as a representation of Deity (not deity but a REPRESENTATION of). In others, the couple imagines that they are deity in the cosmic creative process (if you are a nondualist rather than a monotheistic, this makes sense; if you are a Western Judeo-Christian monotheist, you are doing something contrary to your alleged belief system). In yet others, it is just about transmuting the sex energy and the partner is secondary or irrelevant. If you are Christian and practicing Neotantra with someone other than your marriage partner, that is considerd “fornication,’ anyway, isn’t it? Ultimately, you have to find a rationale that works for you; not follow a trendy paradigm.