No one who has commented above has asked any further questions about your current situation or future ambitions.
I'm not sure you need a finical advisor to be honest, not unless you have some clue of what your objectives are.
Pay off any debt if you have any.
Are you a basic or higher rate tax payer as that will determine whether you get £500 or £1000 a year interest from savings tax free. Whichever one you are find the best paying instant access savings account that will keep you below your annual allowance.
You are in the fortunate position that we are about to enter a new tax year in April, so you can put £20k into an ISA pre and then another £20k when the new tax year starts. If I was in my 20's I'd invest the £40k in a global index tracker with the objective of having it in then for 15-20 years.
You still probably then have £150k left. I'm not usually a fan but you could put £50k into premium bonds, they are tax free and on average you could get a 4% return and they are government backed.
You then still have £100k left. What is your pension situation? I'd strongly consider paying some into a pension. Depending on what rate of taxpayer you are. You can pay in an annual amount up to your annual earnings and will be able to claim the tax relief back which is probably the best investment you can make. Downside is that any pension money is then locked away, possibly until you are 60ish, but then again that's kind of the point.
Spend some. Life is short. Take £10k and assign it as fun money, travel and see stuff. I've never regretted spending a single penny of travel.
Whatever you have left, is likely going to be subject to tax on any returns you make. Where you put it will be down to your risk profile and whether you have any future plans for big expenditure such as a house. You could park it in the best savings account you can an then feed it into future year ISA allowances.
You are young, it's all about balance, but don't fall into the trap of putting it all into cash ISAs and savings accounts. No one builds future wealth that way.