This is almost a free world, everyone and anyone can visit any country in the world regardless of your sexual orientation.You must be aware when choosing your travel destination of which countries openly accept homosexuality and if they do what cities/areas to visit for the best Gar bars and clubs etc.
On the whole Western countries are pretty open to homosexuality whilst Dictatorships, Communist and Middle East countries discourage or make it illegal.
If countries make it technically illegal for homosexuality sometimes the law is not enforced and actually it is a great holiday destination.