Selling the property during Covid and tenant rights

Possession - Section 8 and Section 21

Our tenant is struggling to pay rent due to Covid. We have been very understanding and had mortgage holidays x 2 now. However, we have decided we would like to sell the property this year, to release our investment and put it to other things. Due to changes in rules for notice periods etc, can you offer advice on this? Their tenancy agreement runs out in July, but do we still need to do a S8 or S21? I have suggested rent repayment agreement in past after Lockdown 1 but he has not been able to meet it so we wrote it off, however they are still struggling now and uncertain it will improve. Currently 5 months 3 from Lockdown 1 and 2 months Oct and Dec.
Also can you recommend selling with or without tenant?