What is your overall financial situation?
It sounds like this £10k is all you have, but you are somewhat settled (married, mortgage - kids?) so can't afford to lose it on short term share or cyrpto investments.
Plus you don't have the knowledge atm - if you are interested in doing this start educating yourself now.
What are your pension situations like?
Is this a one of £10k for some reason or money you have accumulated and you'll continue to save and add to each month (how much?).
I'm very risk adverse and carry higher cash levels than is sensible, despite knowing this.
I'd personally put it in premium bonds as my back up fund, in case of emergency need - redundancy etc. If you needed it for something like a boiler or roof repairs it would be quickly accessible, but it isn't just in the bank to be spent.
Premium bond wins are tax free.
The average return (prize rate) isn't great, but then neither are bank accounts.
I'd then look at how much you can save each month and split this between your pension requirements (very long term) and other more more short or medium term goals.
If your employers offer a pension scheme where they will match your contributions then that is free money, and definitely worth looking into.
Otherwise you can probably contribute to your employer scheme anyway, and if you salary sacrifice can benefit from a national insurance saving.
Or standalone personal pensions.
If you want to build up another cash fund then regular savers are a good idea. They carry a higher rate of interest and usually just run for a year at which point they pay out and you start again of you want. Depending on your requirements at the time you could then use those funds (holiday, boiler etc) or add them to one of your other saving vehicles.
Given you've got the £10k backup you could look at putting the medium term money into shares but until you've educated yourself about this I'd stick to funds. You can get trackers very cheaply, covering UK or global funds. You should do this via an ISA as any income and gains would be tax free.
As ISA's are individual you should split this so you each have the same going in.
With interest rates as low as they are and unless you are additional rate taxpayers then you will have a 0% rate interest allowance £1,000 for basic rate taxpayers and £500 for higher rate tax payers). Given this you probably don't have to worry about tax on the interest at this stage.