1. Have a look at
https://www.pumph.co.uk/
2. Its not clear whether the 22 mm pipes are to be terminated below the proposed joints, or a tee is to be inserted.
3. If to be terminated, then as follows:
3a. Obtain hoses, with 28 mm compression one end and female 1" BSP fitting at the other.
3b. Use a short piece of 28 mm pipe to connect valves to compression end.
3c. Measure up where joints will be and cut 22 mm pipes (after isolating any supplies). Make sure flexis won't be kinked.
3d. Obtain 2 off 22 mm to 1" adapters, e.g. BES 9012
3e. Fit compression end of adapters to 22 mm pipe.
3f. Attach 1" BSP female end of flexi to 1" BSP male end of adapter. You will need thread sealant.
4. Things to watch out for:
4a. The pipes mustn't carry anything but water. The yellow handle suggests gas.
4b. Be sure the flexis are rated for continuous operation at the pressures and temperatures which will be involved.
4c. If the source of supply is the 22 mm pipes, fit full bore isolation valves, suitably rated, so that the flexis can be changed.
5. The above suggests a way of doing what you want to do. It is your responsibility to make sure what you are trying to do is safe and legal.