Pension pots invested in the stock or bond markets earn investment returns. Money in interest-bearing accounts earn interest. The word "interest" is used as convenience in these demonstrative examples but it's the same thing.
If they achieve an average 5% return on investment per annum it's the same thing.
OP, you need to stop obsessing over what is shown on your financial services dashboard. It's just a snapshot. It means that if a person retired today with what is in your pot, they would get an annual income of X. It doesn't mean that is what you actually will get 20, 25 or 30 years from now. It's bells and whistles on their website. You aren't retiring today so ignore those numbers.
As we have tried to tell you, your workplace pension pots will grow over the years, and they will not only grow by the amounts you contribute, but by the returns they achieve in the markets.
Get a reputable financial advisor ASAP. They will explain this to you. They will tell you about the investing options. Generally the younger you are, the more aggressive the options you should choose. As you near old age, your money will need to be moved to more stable investment choices that don't fluctuate in value as the stock markets move.
The advisor also will tell you, based on the interest rate of your mortgage vs the average annual returns in the stock market, whether it makes more sense to prepay your mortgage or increase your contributions to your workplace pension. They also will tell you of the tax relief you might achieve by increasing pension contributions, which will make your income go further.
None of this is rocket science. It is nothing to be frightened of.
Phone the HR departments of the entities you used to work for. Tell them you are gathering information for an upcoming meeting with a personal financial advisor and that you need to know your pension status. They get these inquiries all the time and will direct you to the internal or external pension manager. Who in turn should be able to provide you with the account information.
You really need to get on top of this. Money invested today is worth a lot more in the long run than money invested 1, 5 or 10 years from now.