You really shouldn't bring a stray in with other animals unless you've had it checked at the vet first and vaccinated, they could carry fatal diseases. Give them time to acclimate with eachother, don't try to rush it or force it. Let it hide if it wants. If its aggressive keep it isolated.

The new cat needs to be kept in a separate room that the other animals aren't allowed in. It's trying to acclimate to a whole new environment, and if it's a stray then it's extra overwhelmed. After a week or two, if the new cat seems more comfortable, you can start slowly introducing the animals. Open the door to the room and put in a baby gate so the animals can sniff but not hurt each other. Monitor their interactions and reward calm & nice behaviour. The new cat is likely acting out because it's scared and overstimulated, but given a chance to adapt it will most likely come to accept and like your other animals.

It helps if you take something that has the scent of the other pets and let the cat smell them. Like a toy or blanket.
Do the same with the new cat take something with it's scent and let the other animals smell it.

Wow a new record. Everybody agrees. Separate and to the vet. If cleared slowly allow interaction with supervision.
Then again that's what I tell my son about his "new" girlfriends.

Quarantine and vet. Now that's out of the way, when I was a kid we had a cat for several years. Then someone we knew had a dog that had been in a bad home before (she had abandonment issues as a result but was a lovely dog otherwise) and needed a new family. My parents agreed to take her. We moved her in. The cat hadn't really been around dogs before. She hid in the basement for two weeks before finally coming up.
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Later on we ended up with another dog. And, after that cat had passed on, we ended up rescuing two cats. We kept them completely separate the first night and, when they first met, the female cat freaked out around the dogs. Years later and she would actively seek the male dog out to groom her or just to cuddle up with.
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Point is, it will take time, but they will likely get there eventually. You'll just have to be patient, but don't put the other animals' health at risk

Hey. @Serosenpai. I was just making a bad joke. But keep the other pets safe and get a vet to check the new one out. After that take it slowly.

Some cats are "hostile" without being hostile. One of my cats, Levy, will hiss and yowl at my other cat, Ember. She is very mean, but she isn't actually hurting anything but his emotions which is really killing me with the therapy costs.

If it's just yelling a lot, then it may not necessarily be getting ready to fight. This stray may not be doing this exactly so idk. Just giving my own little anecdote of introducing new cats.

Update: my new cat is doing okay, she's not attacking anyone, but she's not exactly ready to meet my dog.