The “collision” with Andromeda is estimated to be in about 4-5 billion years, around the same time that the sun is expected to swell large enough to reach mars.
Yeah, here’s a great video ( < 4 minutes) about it.
The night sky before it and during the collision will be spectacular, but after it all settles, it will be pretty bland!
https://www.youtube.com/watch?v=qnYCpQyRp-4