Welcome to the forum Nuiloa
I have had solitude and live-in companionship intermittently since 2004.
In choronological order...
10 months solitude (widowed), but still w*rking
2 years live-in companionship, both still w*rking
2.5 years live-in companionship (same person), FIREd, so I was alone all day
6 months solitude (break-up), FIREd
8 months live-in companionship, me FIREd, he is retired so we are together most of the day but not 24/7
When I was alone, either living completely alone or just alone all day, I had to really motivate myself to get things done around the house (unassisted) and/or get out and socialize.
I searched for social things for non-seniors to do during the day, and came up pretty empty handed. My age (48 at FIRE in 2007) prevented me from joining certain groups. I'm 53 now and still ineligible for these groups.
So I volunteered to be a driver for the DAV Transportation Network.
I did that for 2 years, off in winter and on in good weather. It got me around people, it was a specific arrival time commitment, and it was very rewarding. I stopped when it was time for me to stop.
Then I helped out at a food bank for several months. I got bored with that very quickly.
These days I hang out at the Legions with Mr B (boyfriend) and meet all sorts of people. Sometimes I stay home, i.e. when he goes solo to periodic meetings.
I am an extrovert, or at least I used to be. I believe I have migrated to a nice balance of enjoying solitude as well as being around people.
So...what I would suggest is to start off doing 1 volunteer or group activity, something you are personally interested in and is age appropriate for you. If that does not suit you, try something else or take some time off from it.
Set your goal to be a balanced mix of alone and social time. It is your time and you will know what w*rks best for YOU.