How to add userid to payload when generate access token usin

Question

problem

How to add UserId to payload when generate access Token Using JWT asp.net core 2.2 ?

i make function generate access token but i need to modify it to have or load userid on payload and get result as json ?

how to do that if possible ?

I need if string userid paramters have values add it to payload of generate access token .

What I have tried:

public string GenerateTokens(string userId)
{
var Claims = new Claim[]
{
new Claim(JwtRegisteredClaimNames.Sub,userId)
};
var signingkey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("this is secret phrase"));
var SigningCredntials = new SigningCredentials();
var Jwt = new JwtSecurityToken();
return new JwtSecurityTokenHandler().WriteToken(Jwt);
}
configure service on startup
public void ConfigureServices(IServiceCollection services)
{
//=================This Setting Related To generate Access Token Data===============
var signingkey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("this is secret phrase"));
services.AddAuthentication(options => {
options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
}).AddJwtBearer(cfg =>
{
cfg.RequireHttpsMetadata = false;
cfg.SaveToken = false;
cfg.TokenValidationParameters = new Microsoft.IdentityModel.Tokens.TokenValidationParameters()
{
IssuerSigningKey = signingkey,
ValidateAudience = false,
ValidateIssuer = false,
ValidateLifetime = false,
ValidateIssuerSigningKey = true
};
});
services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
}