Pension options

Albermarle

I don’t have enough knowledge to be buying and selling shares so will probably just settle on a fund like Vanguard lifestyle 60 or 40.

For the vast majority of pension investors like yourself , it is not in any case recommended to buy individual shares as it is too risky . So some kind of multi asset fund like Vanguard or similar is more normal, or if you have more knowledge you can look at a limited number of different funds/ETF's and investment trusts .
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Fidelity are offering £500 cash back if you transfer your pension to them for my size pot.

You need to transfer £150K to get the £500 cashback .
There are a number of retail SIPP providers in the market with different charging structures.
Those that charge % fee are generally better for sums of £100K and below , such as Fidelity; Hargreaves Landsdown & Aj Bell
Those that charge a flat fee are better for bigger sums, such as Interactive Investor and for cheaper still 'I web '
Be careful though of extra charges for SIPPS with the cheaper ones ( as opposed to non pension investments ) and for drawdown when you take the pension. Only Fidelity and HL have an all in price .
here is a link to a comparison site
https://monevator.com/compare-uk-cheapest-online-brokers/