what if i end up alone

You need to socialize.
Find interests and then seek out groups that share your interests.
Church/Temple/Mosque (whichever applicable) might be a good place to start.
Check your local Library listings for social gatherings or groups with similar interests to yours.

In this way you'll meet like-minded folk you'll already have something in common with.

You could also try volunteering. Another good way to meet people with similar interests.

Three possible pathways occur to me. One, you end up alone and are miserable, in which case I recommend joinding a common interest group, possibly even on line. Or you are not unhappy, in which case you can simply live happily ever after without the responisibilty of keeping a relationaship afloat. Plan B would be to get a dog. At one level the dog will giove you uncritical affection. A secondary benefit being that it will give you someone to talk to, empathise with and just not be alone with..And a reason to go out. Which will place you in potential company of other dog owners..😷

Can you start making friends?

Many seniors rely on neighbours

There are some great books and videos on improving interpersonal skills.

Go out, join a club or do volunteer work.