Thomas' concurrence specifically targets three cases that permitted gay sex, same-sex marriage, and right to contraceptives. He didn't mention interracial marriage (Loving v. Virginia) but he is married to a white woman so maybe sees the need for that right.
I think same-sex marriage is the obvious next target and some state legislatures have already talked about rolling that back. It won 5-4 with Kennedy on the Court, now that both he and Ginsburg are gone, the math is bad. I imagine in the next 30-60 days, we will see where the targets are.
On abortion, we're going to see a flurry of cases as states pass all-out bans, which will be challenged. Even Rehnquist, of all people, didn't think a complete ban on abortion would be possible without a carve out for health of the mother but some of these laws don't have that. So we will see abortion challenges under both state and federal laws. States will presumably begin to pass restrictions on women - can't leave Texas to get an abortion in another state, for example - that will invariably end up before the Supreme Court as well.
As a gentle reminder, I've worked in non-profit law for over twenty years. Most of the heavy lifting on abortion, same-sex rights, immigrant rights, etc are being done by legal nonprofits such as the ACLU, planned parenthood, etc. I know many of the people working in these orgs and they are dedicated to these issues and are ****ing dying right now. Support those groups, donate money, call your congressmen - both state and federal.