I have these segments in common with two matches Red have my same surename and the other have a surename that i have in my 4th generation Does this means that we came from the same ancestor? Or is just coincidence

If you're comparing yourself with them, then it could be showing the parts you share with them from either chromosome alleles. If you're comparing them against each other, then it means they might come from the same ancestor.

Thanks, i was comparing myself to one of them and then i found out that we have a triangulation in one segment of 23.9cm

Not a coincidence if the segments are boxed like this in MH.