Well, this is a complex issue, it has it's biological and it's social side.
I would say the most important thing about any kind of behaviour is how adaptible it is.
For more simple animals the measure of adaptability is how many offsprings they have and how much genetic material they spread. In most cases homosexuality is not adaptible by it's nature, but there are some cases where it is. For example it is found in male gooses that sometimes the two males establish the "relationship" and have homosexual intercourse, also the female gooses throw themselves at the two males so males have sex with them too. As the female gooses give birth to their offsprings, there are now two homosexual (actually more bisexual) male gooses who protect the offspring instead of one heterosexual male goose, and the offsprings have more chances of survival. So that is adaptive.
Humans on the other hand had evolved a lot in a social sense, and we no longer give that much meaning to our genetic material, we give more meaning to our minds, beliefs and values. So maybe today a gay couple in USA can adopt child and raise it with their minds, beliefs and values. And that is not inadaptive... On the other hand a gay couple in Saudi Arabia would be beheaded and that is inadaptible and not natural there. So i would say it depends on the culture where you live. And despite mass propaganda from the both left (LGBT+ community above all) and right (conservatives), the science has no moral, the science is just the facts, and based on the facts it all about adaptability.
The same goes for masturbation. If you can't find the partner at the moment, you should masturbate for your health. On the other side if you masturbate all the time you will lose enthusiasm to look for a partner and will not find one. So you will become a chonic masturbator.
So it is all about wider context, how adaptible is the behaviour. There is not natural vs. unnatural and no right vs. wrong.
And about those people claiming everything is natural and great and should be spread across society because it is found in nature, they have a huge flaw in resoning. The unprovoked murder, pedofilism and intercourse with different species is also found in nature in other species, yet i don't believe you would call that natural when humans did it. And after all, we are also part of the nature, so is the genocide and war natural? I don't have anything aginst masturbation or homosexualty (most of use do the first thing often, and have many friends from second group) but it is terrifing how many people don't think through realisticly stuff like this and are influenced by propaganda. (Thumbs down incoming...)
-Finishing the 3rd year of psychology studies, that is what i have learned about topic.