The term "communist" is almost obsolete.
Nations like Russia/USSR and China were, in their beginning mostly anti-religion and atheist - mostly because Karl Marx described religion as the "opiate of the people". What he meant be this was that the semitic religions (Judaism, Christianity, Islam, etc) taught obedience to authority, thus supporting the wealthy and powerful in exploiting the poor. Slavery and surfdom were typical examples. In the early years, Communists governments banned and persecuted religions.
In China, being gay was never an issue because they were overpopulated and gays tend to have far fewer children; it fitted well with the period of the one-child policy.
However, communist states found it difficult to prevent people from practising the religions they were born into. Eventually Russia permitted its people to worship in the Russian Orthodox Church, although they still tended to persecute Jews. The Russian Church struck a deal with the government to support whoever was in power.
Eventually China opened up to allow all its original religions, Confucianism, Taoism, Buddhism, Christianity and Islam, but only in so far as they did not threaten any aspect of the Communist Party. Any pro-democracy groups are still persecuted. The Tibetans and Weigas are prime examples but there are many others.
All religions (except Buddhism) encourage adults to marry and have families; thus most religions tend to be anti-gay to a greater or lesser extent.
Thus, within communist countries, if a citizen is religious then there is a fair chance that he or she might also be anti-gay AND communist.

In the west, very few leftists are communists. Most who might once have been communists have seen the atrocities committed by Russia and China and have decided that that model of politics doesn't work.
The majority of western lefties aspire to a socialist/liberal democracy - meaning that the government provides free education and medical care for all citizens and has a social safety net to those who are disabled, have lost their job or have reached old age and retirement. In these cultures, most still hold to one of the protestant versions of Christianity, such as Lutheranism. Examples of these are the Scandinavian countries. There, many but not all Lutherans are anti-gay, but for the government and those who are not religious, gayness is not an issue. It is legal, and gays may marry and have kids.
Several European countries, either Catholic or Protestant (France, Germany, Netherlands and Ireland) have also legalised homosexuality.

Broadly speaking, people who support leftist/liberal politics tend to accept gayness and to abhor homophobia.
Likewise most have an inclusive attitude about wanting all people, regardless of race, religion or culture, to have equal rights, opportunities and responsibilities. Thus, most are against sexist, racist, able-ist and age-ist discrimination. They stand against anything that promotes hatred of fellow human beings.

However, the most important thing to remember is that within any group of people there are always lots of exceptions. One cannot assume. Always better to ask the individual what they believe about specific issues and why. This leads to interesting discussions and a deeper understanding of one another.

Feelings -. Nothing more than feelings.
Forgetting human rights is easier for the conservatives.

Much the same as the anti-commies.

Define Communist.
I'm an Anarcho-Communist, not a Marxist and I'm very much pro-LGBT.