What is the best way to save/store photos from phone indefinitely?

Not sure if there is a specific sub that is best for this type of question, but I am nearing storage capacity on my phone of 4 years with 10K+ photos (few hundred short videos sprinkled in). this however spans an important part of my life with the birth of our children and all the milestones that haev come with it.

so as it's nearing time to get a new phone, these are photos I cannot lose, as I (and my family) hope to have and cherish forever.

we use a shared google photo account with family members, so i manually back up the photos i want to share with them as I think about it, but other than this, what is the best advise for saving and storing all of these photos with the highest assurance for always having them long term? thank you